Answer: Thus for the conversion of gray tin to white tin is -20.9 kJ
Explanation:
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The final reaction is
The intermediate balanced chemical reaction will be,
(1)
(2)
substarcting (2) form (1) we get
Answer : The correct answer is 109.
Explanation :
Significant figure : It is defined as the each digits of a number have meaning or contribute to the value of the number.
The addition of given digits is,
43.2 + 50.0 + 16.0 = 109.2
As per the question, the given digits has 3 significant figures. But the answer after addition is 109.2 has 4 significant figures.
The addition rule of significant rule is the least precise number of significant figure in any number of the problem determines the number of significant figures in the answer.
Therefore, from the addition rule, the correct answer is 109.
<span>C. It is in the row below and therefore more reactive </span>
Hello,
I have attached a periodic table to allow you to further understand my answer. We know elements are categorized in groups of Metals, Nonmetals, and metalloids. Let’s analyze each element. Sulfur is a nonmetal which mean it does not conduct well and does not have a good appearance, the same applies to all the other non metals on this list, including sulfur and helium. Copper is our only answer in which it fits and electricity can pass through/conduct easily. So our answer is copper. I hope this helps you with your assignment.