Answer:
Mass = 11 g
Explanation:
Given data:
Mass of Zn = 5 g
Mass of HCl = 50 g
Mass of hydrogen gas produced = 6 g
Mass of zinc chloride produced = ?
Solution:
Chemical equation:
Zn + 2HCl → ZnCl₂ + H₂
Number of moles of Zn:
Number of moles = mass / molar mass
Number of moles = 5 g / 65.38 g/mol
Number of moles = 0.08 mol
Number of moles of HCl :
Number of moles = mass / molar mass
Number of moles = 50 g / 36.5 g/mol
Number of moles = 1.4 mol
Now we will compare the moles of both reactant with zinc chloride.
Zn : ZnCl₂
1 : 1
0.08 : 0.08
HCl : ZnCl₂
2 : 1
1.4 : 1/2×1.4 =0.7 mol
The number of moles of zinc chloride produced by Zn are less so it will limiting reactant.
Mass of zinc chloride:
Mass = number of moles × molar mass
Mass = 0.08 mol × 136.3 g/mol
Mass = 11 g
Answer: emission spectrum
Explanation:
<h3>
Answer:</h3>
81.9 grams
<h3>
Explanation:</h3>
From the question we are given;
- Half-life of C-14 is 5730 years
- Original mass of C-14 (N₀) = 150 grams
- Time taken, t = 5000 years
We are required to determine the mass left after 5000 years
- N = No(1/2)^t/T, where N is the remaining mass, N₀ is the original mass, t is the time taken and T is the half-life.
t/T = 5000 yrs ÷ 5730 yrs
= 0.873
N = 150 g ÷ 0.5^0.873
= 150 g × 0.546
= 81.9 g
Therefore, the mass of C-14 left after 5000 yrs is 81.9 g
Answer:
B. False
Explanation:
All the atoms of an element are not entirely the same no matter where they are found.
The phenomenon of isotopy brings a different perspective to the identity of an element.
- Isotopy is the existence of two or more atoms of the same element having the same atomic number but different mass numbers due to the differences in the number of neutrons in their various nuclei.
- Isotopes of an element have the same electrons but differ in their masses.
- They also differ in their chemical properties.
