15280 + Interview Questions in Chemistry Page 192 InterviewSolution

9551.	Why is aqueous solution of copper sulphate acidic in nature?
Answer» Why is aqueous solution of copper sulphate acidic in nature?

Discussion

9552.	Calculate the pH of a solution obtained by mixing of pH = 4 and 0.2 litre of pH = 10.
Answer» Calculate the pH of a solution obtained by mixing of pH = 4 and 0.2 litre of pH = 10.

Discussion

9553.	When ferrous sulphate is added to a solution of potassium permanganate, it turns colourless. Why?
Answer» When ferrous sulphate is added to a solution of potassium permanganate, it turns colourless. Why?

Discussion

9554.	A first aid manual suggests that vinegar should be used to treat wasp Sting and baking soda for bee stings.1 what does this information tell you about the chemical nature of the wasp Stings. 2. If there were no baking soda in the house, what other household substance could you use to treat bee stings?
Answer» A first aid manual suggests that vinegar should be used to treat wasp Sting and baking soda for bee stings.1 what does this information tell you about the chemical nature of the wasp Stings. 2. If there were no baking soda in the house, what other household substance could you use to treat bee stings?

Discussion

9555.	Anish buried the following in a corner of his garden to dispose (1) A broken eggshell (2) Pencil Shavings (3) Dry leaves (4) Plastic carry bags (5) Fruit and vegetable peels Which of these is most likely to have remained the same?
Answer» Anish buried the following in a corner of his garden to dispose (1) A broken eggshell (2) Pencil Shavings (3) Dry leaves (4) Plastic carry bags (5) Fruit and vegetable peels Which of these is most likely to have remained the same?

Discussion

9556.	The spin quantum number is denoted by ________.
Answer» The spin quantum number is denoted by ________.

Discussion

9557.	The volumes of gases A, B, C and D are in this ratio 1 : 2 : 2 : 4 under the same conditions of temperature and pressure. If the volume of A is actually 5.6 dm3 at STP, calculate the number of molecules in the actual volume of D at STP (Avogadro's number is 6 x 1023). The volume of D is four times the volume of A as given.
Answer» The volumes of gases A, B, C and D are in this ratio 1 : 2 : 2 : 4 under the same conditions of temperature and pressure. If the volume of A is actually 5.6 dm³ at STP, calculate the number of molecules in the actual volume of D at STP (Avogadro's number is 6 x 10²³). The volume of D is four times the volume of A as given.

9557.

The volumes of gases A, B, C and D are in this ratio 1 : 2 : 2 : 4 under the same conditions of temperature and pressure. If the volume of A is actually 5.6 dm3 at STP, calculate the number of molecules in the actual volume of D at STP (Avogadro's number is 6 x 1023). The volume of D is four times the volume of A as given.

Answer»

The volumes of gases A, B, C and D are in this ratio 1 : 2 : 2 : 4 under the same conditions of temperature and pressure.

If the volume of A is actually 5.6 dm³ at STP, calculate the number of molecules in the actual volume of D at STP (Avogadro's number is 6 x 10²³).

The volume of D is four times the volume of A as given.

Discussion

9558.	Q9. Consider the following statements about Shell Companies: 1. They can be set up by business people for legitimate purposes only. 2. Shell companies are companies without active business operations or significant assets. Select the incorrect answer using the codes given:
Answer» Q9. Consider the following statements about Shell Companies: 1. They can be set up by business people for legitimate purposes only. 2. Shell companies are companies without active business operations or significant assets. Select the incorrect answer using the codes given:

9558.

Q9. Consider the following statements about Shell Companies: 1. They can be set up by business people for legitimate purposes only. 2. Shell companies are companies without active business operations or significant assets. Select the incorrect answer using the codes given:

Answer»

Q9. Consider the following statements about Shell Companies:

1. They can be set up by business people for legitimate purposes only.

2. Shell companies are companies without active business operations or significant assets.

Select the incorrect answer using the codes given:

Discussion

9559.	What are mineral acids?
Answer» What are mineral acids?

Discussion

9560.	Iron nails rust in test tube A but they do not rust in test tubes B and C. What inferences can be drawn from the given observations ?
Answer» Iron nails rust in test tube A but they do not rust in test tubes B and C. What inferences can be drawn from the given observations ?

9560.

Iron nails rust in test tube A but they do not rust in test tubes B and C. What inferences can be drawn from the given observations ?

Answer»

Iron nails rust in test tube A but they do not rust in test tubes B and C. What inferences can be drawn from the given observations ?

Discussion

9561.	Which of the following elements is least metallic in nature?
Answer» Which of the following elements is least metallic in nature?

Discussion

9562.	Which is not a cause of destruction of forests?
Answer» Which is not a cause of destruction of forests?

Discussion

9563.	Due to screening effect of electrons in an atom:
Answer» Due to screening effect of electrons in an atom:

Discussion

9564.	Pick up the statements which are related to carbon: 1. 14th group element. 2. In the human body, it is second most abundant element by mass after oxygen. 3. Non-metallic in nature. 4. 15th group element. 5. One of the few elements known since antiquity. 6. Only 4 electrons are available for bonding. 7. Only 3 electrons are available for bonding. 8. Metallic in nature.
Answer» Pick up the statements which are related to carbon: 1. $14^{t h}$ group element. 2. In the human body, it is second most abundant element by mass after oxygen. 3. Non-metallic in nature. 4. $15^{t h}$ group element. 5. One of the few elements known since antiquity. 6. Only 4 electrons are available for bonding. 7. Only 3 electrons are available for bonding. 8. Metallic in nature.

9564.

Pick up the statements which are related to carbon: 1. 14th group element. 2. In the human body, it is second most abundant element by mass after oxygen. 3. Non-metallic in nature. 4. 15th group element. 5. One of the few elements known since antiquity. 6. Only 4 electrons are available for bonding. 7. Only 3 electrons are available for bonding. 8. Metallic in nature.

Answer»

Pick up the statements which are related to carbon:

1. $14^{t h}$ group element.

2. In the human body, it is second most abundant element by mass after oxygen.

3. Non-metallic in nature.

4. $15^{t h}$ group element.

5. One of the few elements known since antiquity.

6. Only 4 electrons are available for bonding.

7. Only 3 electrons are available for bonding.

8. Metallic in nature.

Discussion

9565.	Explain esterification reaction with the help of a chemical equation. Describe an activity to show esterification.
Answer» Explain esterification reaction with the help of a chemical equation. Describe an activity to show esterification.

Discussion

9566.	Some hunters are roaming in the lush green forest of Africa. They spot a deer and kill it. They decide to roast the deer there and then and eat it. When the hunters had just finished enjoying the feast of roasted deer, a lion attacks them. The lion kills one of the hunters and eats his flesh. (a) Write a food chain which provides food to the lion in this case. (b) Which animal (other than deer) the lion could look for food if he did not get the hunter as prey? (c) Which other animals in the forest could have been in place of the lion? (d) How does the above food chain differ from the food chain such as plants→goat→man?
Answer» Some hunters are roaming in the lush green forest of Africa. They spot a deer and kill it. They decide to roast the deer there and then and eat it. When the hunters had just finished enjoying the feast of roasted deer, a lion attacks them. The lion kills one of the hunters and eats his flesh. (a) Write a food chain which provides food to the lion in this case. (b) Which animal (other than deer) the lion could look for food if he did not get the hunter as prey? (c) Which other animals in the forest could have been in place of the lion? (d) How does the above food chain differ from the food chain such as $p l a n t s \to g o a t \to m a n$ ?

9566.

Some hunters are roaming in the lush green forest of Africa. They spot a deer and kill it. They decide to roast the deer there and then and eat it. When the hunters had just finished enjoying the feast of roasted deer, a lion attacks them. The lion kills one of the hunters and eats his flesh. (a) Write a food chain which provides food to the lion in this case. (b) Which animal (other than deer) the lion could look for food if he did not get the hunter as prey? (c) Which other animals in the forest could have been in place of the lion? (d) How does the above food chain differ from the food chain such as plants→goat→man?

Answer»

Some hunters are roaming in the lush green forest of Africa. They spot a deer and kill it. They decide to roast the deer there and then and eat it. When the hunters had just finished enjoying the feast of roasted deer, a lion attacks them. The lion kills one of the hunters and eats his flesh.

(a) Write a food chain which provides food to the lion in this case.

(b) Which animal (other than deer) the lion could look for food if he did not get the hunter as prey?

(c) Which other animals in the forest could have been in place of the lion?

(d) How does the above food chain differ from the food chain such as $p l a n t s \to g o a t \to m a n$ ?

Discussion

9567.	A hydrocarbon having one double bond has 100 carbon atoms in its molecule. The number of hydrogen atoms in its molecule will be : (a) 200 (b) 198 (c) 202 (d) 196
Answer» A hydrocarbon having one double bond has 100 carbon atoms in its molecule. The number of hydrogen atoms in its molecule will be : (a) 200 (b) 198 (c) 202 (d) 196

Discussion

9568.	When a solution is added to a cloth strip treated with onion extract, then the smell of onion cannot be detected. State whether the given solution contains an acid or a base.
Answer» When a solution is added to a cloth strip treated with onion extract, then the smell of onion cannot be detected. State whether the given solution contains an acid or a base.

Discussion

9569.	Hydrogen is not a metal then why is it kept in the reactivity series?
Answer» Hydrogen is not a metal then why is it kept in the reactivity series?

Discussion

9570.	What is salts
Answer» What is salts

Discussion

9571.	Why is fourth bond not possible?
Answer» Why is fourth bond not possible?

Discussion

9572.	How is the method of extraction of metal high up in the reactivity series different from that for metals in the middle? Why the same process can't be applied for them ? Explain giving equations the extraction of sodium?
Answer» How is the method of extraction of metal high up in the reactivity series different from that for metals in the middle? Why the same process can't be applied for them ? Explain giving equations the extraction of sodium?

Discussion

9573.	What are the properties of acetic acid?
Answer» What are the properties of acetic acid?

Discussion

9574.	Why does sulphuric acid act like a dehydating agent?
Answer» Why does sulphuric acid act like a dehydating agent?

Discussion

9575.	Glass can be etched or scratched by which of the following materials? (1) Diamond (2) Hydrofluoric acid (3) Aquaregia (4) conc. Sulphuric acid Code:
Answer» Glass can be etched or scratched by which of the following materials? (1) Diamond (2) Hydrofluoric acid (3) Aquaregia (4) conc. Sulphuric acid Code:

9575.

Glass can be etched or scratched by which of the following materials? (1) Diamond (2) Hydrofluoric acid (3) Aquaregia (4) conc. Sulphuric acid Code:

Answer»

Glass can be etched or scratched by which of the following materials?

(1) Diamond (2) Hydrofluoric acid

(3) Aquaregia (4) conc. Sulphuric acid

Code:

Discussion

9576.	Protective mechanical barrier include_________.
Answer» Protective mechanical barrier include_________.

Discussion

9577.	Question 5.2 Translate the following statement into chemical equation and then balance it: Hydrogen sulphide gas burns in air to give water and sulphur dioxide.
Answer» Question 5.2 Translate the following statement into chemical equation and then balance it: Hydrogen sulphide gas burns in air to give water and sulphur dioxide.

Discussion

9578.	Which of the following is true regarding a Leclanche Cell?
Answer» Which of the following is true regarding a Leclanche Cell?

Discussion

9579.	Sonali was performing a experiment in which metal X which was of reddish brown colour, when heated in the presence of oxygen it forms a black coloured compound Y which was basic in nature. When this is again heated in the presence of hydrogen gas it gives back the substance X. Identify the X and Y?
Answer» Sonali was performing a experiment in which metal X which was of reddish brown colour, when heated in the presence of oxygen it forms a black coloured compound Y which was basic in nature. When this is again heated in the presence of hydrogen gas it gives back the substance X. Identify the X and Y?

Discussion

9580.	Which of the following compound is not aromatic?
Answer» Which of the following compound is not aromatic?

Discussion

9581.	Acetaldehyde and acetone are isomers.
Answer» Acetaldehyde and acetone are isomers.

Discussion

9582.	Identify the incorrect formula from the following options.
Answer» Identify the incorrect formula from the following options.

Discussion

9583.	Calculate the volume of oxygen at STP required for the complete combustion of 100 litres of carbon monoxide at the same temperature and pressure. 2CO+O2⟶2CO2 (b) 200cm3 of hydrogen and 150 cm of oxygen are mixed and ignited, as per the following reaction, 2H2+O2⟶2H2O. What volume of oxygen remains unreacted?
Answer» Calculate the volume of oxygen at STP required for the complete combustion of 100 litres of carbon monoxide at the same temperature and pressure. $2 C O + O_{2} ⟶ 2 C O_{2}$ (b) $200 c m^{3}$ of hydrogen and 150 cm of oxygen are mixed and ignited, as per the following reaction, $2 H_{2} + O_{2} ⟶ 2 H_{2} O$ . What volume of oxygen remains unreacted?

9583.

Calculate the volume of oxygen at STP required for the complete combustion of 100 litres of carbon monoxide at the same temperature and pressure. 2CO+O2⟶2CO2 (b) 200cm3 of hydrogen and 150 cm of oxygen are mixed and ignited, as per the following reaction, 2H2+O2⟶2H2O. What volume of oxygen remains unreacted?

Answer»

Calculate the volume of oxygen at STP required for the complete combustion of 100 litres of carbon monoxide at the same temperature and pressure.

$2 C O + O_{2} ⟶ 2 C O_{2}$

(b) $200 c m^{3}$ of hydrogen and 150 cm of oxygen are mixed and ignited, as per the following reaction,

$2 H_{2} + O_{2} ⟶ 2 H_{2} O$ . What volume of oxygen remains unreacted?

Discussion

9584.	Chlorine in the Periodic Table is surrounded by the elements with atomic number 9, 16, 18 and 35. (a) Which of these have Physical and Chemical properties resembling chlorine ? (b) Which is more electronegative than chlorine ?
Answer» Chlorine in the Periodic Table is surrounded by the elements with atomic number 9, 16, 18 and 35. (a) Which of these have Physical and Chemical properties resembling chlorine ? (b) Which is more electronegative than chlorine ?

9584.

Chlorine in the Periodic Table is surrounded by the elements with atomic number 9, 16, 18 and 35. (a) Which of these have Physical and Chemical properties resembling chlorine ? (b) Which is more electronegative than chlorine ?

Answer»

Chlorine in the Periodic Table is surrounded by the elements with atomic number 9, 16, 18 and 35.

(a) Which of these have Physical and Chemical properties resembling chlorine ?

(b) Which is more electronegative than chlorine ?

Discussion

9585.	Match the following : Element/SubstanceAtomicity(i)Hydrogen(A)3(ii)Argon(B)6(iii)Sulphur(C)Diatomic(iv)Carbon dioxide(D)Monoatomic(v)Ammonium Chloride(E)Polyatomic
Answer» Match the following : $\begin{matrix} E l e m e n t / S u b s t a n c e & A t o m i c i t y (i) H y d r o g e n & (A) 3 (i i) A r g o n & (B) 6 (i i i) S u l p h u r & (C) D i a t o m i c (i v) C a r b o n d i o x i d e & (D) M o n o a t o m i c (v) A m m o n i u m C h l o r i d e & (E) P o l y a t o m i c \end{matrix}$

9585.

Match the following : Element/SubstanceAtomicity(i)Hydrogen(A)3(ii)Argon(B)6(iii)Sulphur(C)Diatomic(iv)Carbon dioxide(D)Monoatomic(v)Ammonium Chloride(E)Polyatomic

Answer»

Match the following :

$\begin{matrix} E l e m e n t / S u b s t a n c e & A t o m i c i t y (i) H y d r o g e n & (A) 3 (i i) A r g o n & (B) 6 (i i i) S u l p h u r & (C) D i a t o m i c (i v) C a r b o n d i o x i d e & (D) M o n o a t o m i c (v) A m m o n i u m C h l o r i d e & (E) P o l y a t o m i c \end{matrix}$

Discussion

9586.	What is the formula for Iron oxide and copper chloride?
Answer» What is the formula for Iron oxide and copper chloride?

Discussion

9587.	(a) Calculate the mass of nitrogen supplied to the soil by 5 kg of urea [CO(NH2)2] [O=16:N=14;C=12;H=1] (b) Calculate the volume occupied by 320 g of sulphur dioxide at STP [S=32;O=16]
Answer» (a) Calculate the mass of nitrogen supplied to the soil by 5 kg of urea $[C O (N H_{2})_{2}]$ $[O = 16 : N = 14; C = 12; H = 1]$ (b) Calculate the volume occupied by 320 g of sulphur dioxide at STP $[S = 32; O = 16]$

Discussion

9588.	Give reasons for the following : (a) Sulphuric acid forms two types of salts with NaOH, (b) Red brown vapours are produced when concentrated sulphuric acid is added to hydrogen bromide, (c) A piece of wood becomes black when concentrated sulphuric acid is poured on it, (d) Brisk effervescence is seen when oil of vitriol is added to sodium carbonate.
Answer» Give reasons for the following : (a) Sulphuric acid forms two types of salts with NaOH, (b) Red brown vapours are produced when concentrated sulphuric acid is added to hydrogen bromide, (c) A piece of wood becomes black when concentrated sulphuric acid is poured on it, (d) Brisk effervescence is seen when oil of vitriol is added to sodium carbonate.

9588.

Give reasons for the following : (a) Sulphuric acid forms two types of salts with NaOH, (b) Red brown vapours are produced when concentrated sulphuric acid is added to hydrogen bromide, (c) A piece of wood becomes black when concentrated sulphuric acid is poured on it, (d) Brisk effervescence is seen when oil of vitriol is added to sodium carbonate.

Answer»

Give reasons for the following :

(a) Sulphuric acid forms two types of salts with NaOH,

(b) Red brown vapours are produced when concentrated sulphuric acid is added to hydrogen bromide,

(c) A piece of wood becomes black when concentrated sulphuric acid is poured on it,

(d) Brisk effervescence is seen when oil of vitriol is added to sodium carbonate.

Discussion

9589.	Using electron- dot diagram which show only the outermost shell electrons, show how a molecule o nitrogen, N2, is formed from two nitrogen atoms. What name is given to this type of bonding? (Atomic number of nitrogen is 7)
Answer» Using electron- dot diagram which show only the outermost shell electrons, show how a molecule o nitrogen, $N_{2}$ , is formed from two nitrogen atoms. What name is given to this type of bonding? (Atomic number of nitrogen is 7)

Discussion

9590.	The fraction of heat energy converted into useful mechanical work is called ___ of the heat engine.
Answer» The fraction of heat energy converted into useful mechanical work is called ___ of the heat engine.

Discussion

9591.	A bromine atom attached to the ethane molecule can be named as ___
Answer» A bromine atom attached to the ethane molecule can be named as ___

Discussion

9592.	Complete the following reaction Cu + HNO3→Cu(NO3)2 + H2O +
Answer» Complete the following reaction $Cu + {HNO}_{3} \to Cu ({NO}_{3})_{2} + H_{2} O +$

Discussion

9593.	Write equation for the reaction of: (a) sodium with oxygen (b) magnesium with oxygen
Answer» Write equation for the reaction of: (a) sodium with oxygen (b) magnesium with oxygen

Discussion

9594.	___(Ethanol/ Ethane) is used in anti-bacterial items
Answer» ___(Ethanol/ Ethane) is used in anti-bacterial items

Discussion

9595.	Given the ground state energy E0=−13.6eV and Bohr radius a0 = 0.53 A . Find out how the de Broglie wavelength associated with the electron orbiting in the ground state would change when it jumps into the first excited state.
Answer» Given the ground state energy $E_{0} = - 13.6 e V$ and Bohr radius $a_{0}$ = 0.53 A . Find out how the de Broglie wavelength associated with the electron orbiting in the ground state would change when it jumps into the first excited state.

Discussion

9596.	What is the formula of sodium nitrate?
Answer» What is the formula of sodium nitrate?

Discussion

9597.	Identify the given compound.
Answer» Identify the given compound.

9597.

Identify the given compound.

Answer»

Identify the given compound.

Discussion

9598.	From the standpoint of atomic structure, what determines which element will be first and which the last in a period of the periodic table ?
Answer» From the standpoint of atomic structure, what determines which element will be first and which the last in a period of the periodic table ?

Discussion

9599.	4.0 g of NaOH contained in one deciliter of a solution. Calculate the following in this solution: (i) Mole fraction of NaOH (ii) Molality of NaOH (iii) Molality of NaOH (iii) Molarity of NaOH. (At. wt. of Na = 23, O = 16; Density of NaOH solution is 1.038 g/cm3).
Answer» 4.0 g of NaOH contained in one deciliter of a solution. Calculate the following in this solution: (i) Mole fraction of NaOH (ii) Molality of NaOH (iii) Molality of NaOH (iii) Molarity of NaOH. (At. wt. of Na = 23, O = 16; Density of NaOH solution is 1.038 $g / c m^{3}$ ).

Discussion

9600.	When you use a universal indicator, you see that solutions of different acids produce different colours. Indeed, solutions of the same acid with different concentrations will also give different colours, Why?
Answer» When you use a universal indicator, you see that solutions of different acids produce different colours. Indeed, solutions of the same acid with different concentrations will also give different colours, Why?

Discussion

Explore topic-wise InterviewSolutions in .

Why is aqueous solution of copper sulphate acidic in nature?

Calculate the pH of a solution obtained by mixing of pH = 4 and 0.2 litre of pH = 10.

When ferrous sulphate is added to a solution of potassium permanganate, it turns colourless. Why?

Anish buried the following in a corner of his garden to dispose (1) A broken eggshell (2) Pencil Shavings (3) Dry leaves (4) Plastic carry bags (5) Fruit and vegetable peels Which of these is most likely to have remained the same?

The spin quantum number is denoted by ________.

Q9. Consider the following statements about Shell Companies: 1. They can be set up by business people for legitimate purposes only. 2. Shell companies are companies without active business operations or significant assets. Select the incorrect answer using the codes given:

What are mineral acids?

Iron nails rust in test tube A but they do not rust in test tubes B and C. What inferences can be drawn from the given observations ?

Which of the following elements is least metallic in nature?

Which is not a cause of destruction of forests?

Due to screening effect of electrons in an atom:

Explain esterification reaction with the help of a chemical equation. Describe an activity to show esterification.

A hydrocarbon having one double bond has 100 carbon atoms in its molecule. The number of hydrogen atoms in its molecule will be : (a) 200 (b) 198 (c) 202 (d) 196

When a solution is added to a cloth strip treated with onion extract, then the smell of onion cannot be detected. State whether the given solution contains an acid or a base.

Hydrogen is not a metal then why is it kept in the reactivity series?

What is salts

Why is fourth bond not possible?

How is the method of extraction of metal high up in the reactivity series different from that for metals in the middle? Why the same process can't be applied for them ? Explain giving equations the extraction of sodium?

What are the properties of acetic acid?

Why does sulphuric acid act like a dehydating agent?

Glass can be etched or scratched by which of the following materials? (1) Diamond (2) Hydrofluoric acid (3) Aquaregia (4) conc. Sulphuric acid Code:

Protective mechanical barrier include_________.

Question 5.2 Translate the following statement into chemical equation and then balance it: Hydrogen sulphide gas burns in air to give water and sulphur dioxide.

Which of the following is true regarding a Leclanche Cell?

Sonali was performing a experiment in which metal X which was of reddish brown colour, when heated in the presence of oxygen it forms a black coloured compound Y which was basic in nature. When this is again heated in the presence of hydrogen gas it gives back the substance X. Identify the X and Y?

Which of the following compound is not aromatic?

Acetaldehyde and acetone are isomers.

Identify the incorrect formula from the following options.

Chlorine in the Periodic Table is surrounded by the elements with atomic number 9, 16, 18 and 35. (a) Which of these have Physical and Chemical properties resembling chlorine ? (b) Which is more electronegative than chlorine ?

Match the following : Element/SubstanceAtomicity(i)Hydrogen(A)3(ii)Argon(B)6(iii)Sulphur(C)Diatomic(iv)Carbon dioxide(D)Monoatomic(v)Ammonium Chloride(E)Polyatomic

What is the formula for Iron oxide and copper chloride?

(a) Calculate the mass of nitrogen supplied to the soil by 5 kg of urea [CO(NH2)2] [O=16:N=14;C=12;H=1] (b) Calculate the volume occupied by 320 g of sulphur dioxide at STP [S=32;O=16]

Using electron- dot diagram which show only the outermost shell electrons, show how a molecule o nitrogen, N2, is formed from two nitrogen atoms. What name is given to this type of bonding? (Atomic number of nitrogen is 7)

The fraction of heat energy converted into useful mechanical work is called ___ of the heat engine.

A bromine atom attached to the ethane molecule can be named as ___

Complete the following reaction Cu + HNO3→Cu(NO3)2 + H2O +

Write equation for the reaction of: (a) sodium with oxygen (b) magnesium with oxygen

___(Ethanol/ Ethane) is used in anti-bacterial items

Given the ground state energy E0=−13.6eV and Bohr radius a0 = 0.53 A . Find out how the de Broglie wavelength associated with the electron orbiting in the ground state would change when it jumps into the first excited state.

What is the formula of sodium nitrate?

Identify the given compound.

From the standpoint of atomic structure, what determines which element will be first and which the last in a period of the periodic table ?

4.0 g of NaOH contained in one deciliter of a solution. Calculate the following in this solution: (i) Mole fraction of NaOH (ii) Molality of NaOH (iii) Molality of NaOH (iii) Molarity of NaOH. (At. wt. of Na = 23, O = 16; Density of NaOH solution is 1.038 g/cm3).

When you use a universal indicator, you see that solutions of different acids produce different colours. Indeed, solutions of the same acid with different concentrations will also give different colours, Why?