Question
Give two examples of reduction.
✓
Answer
(1) When hydrogen gas is passed over black copper oxide a reddish coloured layer of copper is formed.
In this reaction an oxygen atom removed from $CuO$ to form copper, hence, this is reduction.
$
\underset{\text { Copper oxide }}{ CuO _{( s )}}+ H _{2( g )} \rightarrow \underset{\text { Coper }}{ Cu _{( s )}}+ H _2 O _{ a )}
$
(2) When hydrogen gas is passed over red hot coke, methane is obtained. Here, hydrogen is added to coke (carbon). Hence, this is reduction.
$
\underset{\text { Carbon }}{ C _{ s )}}+\underset{\text { Hydrogen gas }}{2 H _{2( g )}} \rightarrow \underset{\text { Methane }}{ CH _{4( g )}}
$
In this reaction an oxygen atom removed from $CuO$ to form copper, hence, this is reduction.
$
\underset{\text { Copper oxide }}{ CuO _{( s )}}+ H _{2( g )} \rightarrow \underset{\text { Coper }}{ Cu _{( s )}}+ H _2 O _{ a )}
$
(2) When hydrogen gas is passed over red hot coke, methane is obtained. Here, hydrogen is added to coke (carbon). Hence, this is reduction.
$
\underset{\text { Carbon }}{ C _{ s )}}+\underset{\text { Hydrogen gas }}{2 H _{2( g )}} \rightarrow \underset{\text { Methane }}{ CH _{4( g )}}
$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
If the bulb of 60 W is connected across a source of 220 V, find the electric current drawn by it.
Define functional group and complete the following table:
| Functional group | Compound | Formula |
| ——————– | Ethyl alcohol | ——————– |
| ——————– | Acetaldehyde | ——————– |
Is the number of shells the same in these?
What are the advantages of nuclear energy?
Why does an object released from the hand, fall on the earth?
What is meant by carbon dating method?
Absolute humidity and Relative humidity.
An electric iron rated 750 W operates 2 hours/ day. If the cost of unit is ₹ 3.00 per kWh. Find the cost of energy to operate electric iron for 30 days.
Bacteria have a simpler body plan when compared with human beings. Does it mean that human beings are more evolved than bacteria? Explain your answer.
Observe the given animal and answer the following questions:
i. Identify the given animal and its phylum.
ii. Write any two characteristics of that phylum.
i. Identify the given animal and its phylum.
ii. Write any two characteristics of that phylum.