Answer:
A) 14. 25 × 10²³ Carbon atoms
B) 34.72 grams
Explanation:
1 molecule of Propane has 3 atoms of Carbon and 8 atoms of Hydrogen.
The sample has 3.84 × 10²⁴ H atoms.
If 8 atoms of Hydrogrn are present in 1 molecule of propane.
3.84 × 10²⁴ H atoms are present in

<u>= 4.75 × 10²³ molecules of Propane</u>.
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No. of Carbon atoms in 1 molecule of propane = 3
=> C atoms in 4.75× 10²³ molecules of Propane = 3 × 4.75 × 10²³
<u>= 14.25 × 10²³ </u>
<u>________________________________________</u>
<u>Gram</u><u> </u><u>Molecular</u><u> </u><u>Mass</u><u> </u><u>of</u><u> </u><u>Propane</u><u>(</u><u>C3H8</u><u>)</u>
= 3 × 12 + 8 × 1
= 36 + 8
= 44 g
1 mole of propane weighs 44g and has 6.02× 10²³ molecules of Propane.
=> 6.02 × 10²³ molecules of Propane weigh = 44 g
=> 4. 75 × 10²³ molecules of Propane weigh =



<u>= 34.72 g</u>
Answer: (3) silicon
Explanation:
Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Silicon (Si)
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: ethane
, propanone
and water 
Answer:
Explanation:
Translated:
Calculate the amount of sugar (C12 H22 O11) in the morning tea if a teaspoon contains 5g of sugar?
Given parameters
Mass of sugar = 5g
Unknown:
Amount of the sugar =?
Solution:
A mole is the amount of substance that contains avogadro's number of particles i.e 6.02 x 10²³
Therefore, to find the number of moles contained in the teaspoon of sugar we use the expression below:
Number of moles = 
Molar mass of C₁₂H₂₂O₁₁ = (12x12) + (1x22) + (16x11) = 342g/mol
Number of moles =
= 0.015mol of sugar
or 0.015 x 6.02 x 10²³, 8.8x10²¹atoms of sugar
Answer: A. Pollutants
Explanation:
"A pollutant is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. ..." - Wikipedia
Chlorine-35 and 37 both have the same number of protons. Chlorine-37 has two more neutrons.
hope this helps!
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