Iron nails are dipped into blue copper sulphate solution. After sometime, iron nails are:

Consider the following reactions:

$Z{n}_{\left(s\right)} + CuS{O}_{4\left(aq\right)}\to$
$F{e}_{\left(s\right)}+ ZnS{O}_{4\left(aq\right)}\to$
$Z{n}_{\left(s\right)}+ FeS{O}_{4\left(aq\right)}\to$

Which of the above chemical reaction(s) will take place?

Consider the following reaction:

$CuO + H_2\stackrel{Heat}{\to } Cu + H_{2}O$   

Which species get oxidized in the given chemical reaction?

Consider the following statements:

1. Reactions in which heat is released along with the formation of products are called exothermic chemical reactions.
2. Reactions in which energy is absorbed, are known as endothermic reactions.

Which of the statements given above is/are correct?

The iron blade of various tools such as a cart wheel has a ring in which the wooden handle is fixed. Normally, the ring is slightly smaller in size than a wooden handle. Which of the following principles is used to fix the ring?

Match Column I with Column II and choose the correct option.

Student (X) has taken five $100 mL$ beakers and labelled them A, B, C, D and E and also added $50 mL$ of water in each beaker. After that, she added the following composition of substance in each beaker. It is as follows:

Beaker A: Copper sulphate $\left(CuS{O}_4\right)$+ Zinc granule $\left(Zn\right)$
Beaker B: Copper sulphate $\left(CuS{O}_4\right)$+ Iron nail $\left(Fe\right)$
Beaker C: Zinc sulphate $\left(ZnS{0}_4\right)$+ Copper turnings $\left(Cu\right)$
Beaker D: Iron sulphate $\left(FeS{0}_4\right)$+ Copper turnings $\left(Cu\right)$
Beaker E: Zinc sulphate $\left(ZnS{0}_4\right)$+ Iron nail $\left(Fe\right)$.

Which of the following concepts is used to study the given reactions?

When a copper vessel is exposed to moist air for long, it acquires a dull green coating. The green coating is due to:

1. formation of $\left[Cu{\left(OH\right)}_2\right]$
2. formation of $CuC{O}_3$
3. formation of $CuHC{O}_3$
4. Both (1) and (2)

Codes:
A  B C  D

Consider the following statements:

1. Latent means hidden.
2. The amount of heat energy that is required to change 1 kg of a solid into liquid at atmospheric pressure at its melting point is known as the latent heat of fusion.
3. Water vapor at 273 K (100 degrees C) has more energy than water at the same temperature.

Choose the correct statements: