Answer:
D =Average atomic mass = 10.801 amu.
5) True
Explanation:
Abundance of B¹⁰= 19.9%
Abundance of B¹¹ = 80.1%
Atomic mass of B¹⁰ = 10 amu
Atomic mass of B¹¹ = 11 amu
Average atomic mass = ?
Solution:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) / 100
Average atomic mass = (10×19.9)+(11×80.1) /100
Average atomic mass = 199 + 881.1 / 100
Average atomic mass = 1080.1 / 100
Average atomic mass = 10.801 amu.
2)A chemical reaction is one in which a new elements is created
True
False
Answer:
In chemical reaction new substances are created.
For example:
Photosynthesis:
It is the process in which in the presence of sun light and chlorophyll by using carbon dioxide and water plants produce the oxygen and glucose.
Carbon dioxide + water + energy → glucose + oxygen
water is supplied through the roots, carbon dioxide collected through stomata and sun light is capture by chloroplast.
Chemical equation:
6H₂O + 6CO₂ + energy → C₆H₁₂O₆ + 6O₂
it is known from balanced chemical equation that 6 moles of carbon dioxide react with the six moles of water and created one mole of glucose and six mole of oxygen.
Given :
A certain compound contains 4.0 g of calcium and 7.1 g of chlorine.
Its relative molecular mass is 111.
To Find :
Its empirical and molecular formulas.
Solution :
Moles of calcium , 
.
Moles of chlorine , 
.
The ratio calcium and chlorine is 1 : 2 .
So , the empirical formula is 
.
Now , molecular mass of is :
So , 
Therefore , the molecular formula is also .
Hence , this is the required solution .
Answer:
Empirical formula is CCl₄
Explanation:
Given data:
Percentage of carbon = 7.70%
Percentage of chlorine = 92.3%
Empirical formula = ?
Solution:
Number of gram atoms of Cl = 92.3 / 35.5 = 2.6
Number of gram atoms of C = 7.70 / 12 = 0.64
Atomic ratio:
C : Cl
0.64/0.64 : 2.6/0.64
1 : 4
C : Cl = 1 : 4
Empirical formula is CCl₄.
Answer:
The answer is
<h2>22 g/mL</h2>
Explanation:
The density of a substance can be found by using the formula
From the question
mass of liquid = 44 g
volume = 2 mL
The density of the liquid is
We have the final answer as
<h3>22 g/mL</h3>
Hope this helps you
