<u>Answer:</u> The change in temperature is 84.7°C
<u>Explanation:</u>
To calculate the change in temperature, we use the equation:

where,
q = heat absorbed = 1 kCal = 1000 Cal (Conversion factor: 1 kCal = 1000 Cal)
m = mass of steel = 100 g
c = specific heat capacity of steel = 0.118 Cal/g.°C
= change in temperature = ?
Putting values in above equation, we get:

Hence, the change in temperature is 84.7°C
Answer: 6.25 mol
Explanation:
From the reaction that produces water from its elements (shown in the image), we know that for every mole of oxygen gas consumed, 2 moles of water are produced.
This means that 12.5/2=<u>6.25 mol</u> of oxygen gas is needed.
Answer:
E. Gain of electrons
Explanation:
A reduction reaction is one part of the two concurrent reactions that take place in a redox (reduction-oxidation) reaction.
During reduction, an atom gains electrons from a donor atom, and it's oxidation number becomes smaller.
Option A is wrong because reduction does not increase oxidation state nor are neutrons involved
Option B is wrong because reduction is not a nuclear reaction (does not involve the nucleons)
Option C is wrong because reduction leads to reduction in oxidation state
Option D is wrong leads to a reduction in oxidation state when electrons are gained
Option E is correct because reduction involves gain of electrons