The same number of valence electrons exists in the same family of elements in the periodic table. In finding the answer to this problem, we just have to find the pair that belongs to the same family in the periodic table. The same family means same column. Among these, Oxygen and lead (Pb) are in the same family. This pair is the answer.
Answer:
2.74 x 1023 molecules of CO2.
Explanation:
There are 2.74 x 1023 molecules of CO2.
<h3><u>Answer;</u></h3>
2, Blank, 2 ;
<h3><u>Explanation;</u></h3>
The balanced chemical equation would be;
2 CO + O2 → 2 CO2
Balancing a chemical equation ensures that the number of atoms of each element are equal on both the reactants side and the products side. This ensures that the law of conservation of mass is obeyed in chemical reactions.
The periodic table increases as you read left to right so it is A.
Answer:
0.55 mol Au₂S₃
Explanation:
Normally, we would need a balanced equation with masses, moles, and molar masses, but we can get by with a partial equation, if the S atoms are balanced.
1. Gather all the information in one place:
M_r: 34.08
Au₂S₃ + … ⟶ 3H₂S + …
m/g: 56
2. Calculate the moles of H₂S
Moles of H₂S = 56 g H₂S × (34.08 g H₂S/1 mol H₂S)
= 1.64 mol H₂S
3. Calculate the moles of Au₂S₃
The molar ratio is 1 mol Au₂S₃/3 mol H₂S.
Moles of Au₂S₃ = 1.64 mol H₂S × (1 mol Au₂S₃/3 mol H₂S)
= 0.55 mol Au₂S₃