Answer:
Explanation:
1) How many moles are 1.55 × 10²⁷ atoms of zinc?
Answer:
0.26 × 10⁴ mole
Explanation:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 1.55 × 10²⁷ atoms of zinc:
1.55 × 10²⁷ atoms × 1 mole/ 6.022 × 10²³ atoms
0.26 × 10⁴ mole
2) How many atoms are in 25.0 moles of calcium?
Answer:
150.55 × 10²³ atoms.
Explanation:
According to Avogadro number,
one mole of substance = 6.022 × 10²³ atoms
The number 6.022 × 10²³ is called Avogadro number.
For 25.0 moles of calcium:
one mole of calcium = 6.022 × 10²³ atoms
25.0 mole × 6.022 × 10²³ atoms /1 mole
150.55 × 10²³ atoms.
So 25.0 moles of calcium contain 150.55 × 10²³ atoms.
3) = How many atoms are in 0.35 moles of carbon?
Answer:
2.12× 10²³ atoms.
Explanation:
According to Avogadro number,
one mole of substance = 6.022 × 10²³ atoms
The number 6.022 × 10²³ is called Avogadro number.
For 0.35 moles of carbon:
one mole of carbon = 6.022 × 10²³ atoms
0.35 mole × 6.022 × 10²³ atoms /1 mole
2.12× 10²³ atoms.
So 0.35 moles of carbon contain 2.12× 10²³ atoms.
4 ) How many moles are 7.6 × 10²⁴ atoms of hellium?
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 7.6 × 10²⁴ atoms of hellium:
7.6 × 10²⁴ atoms × 1 mole/ 6.022 × 10²³ atoms
12. 6 mole
<em>Mass - Mole conversion:</em>
How many moles in 28.0 gram of oxygen?
Answer:
1.75 mol
Explanation:
Given data:
Mass of oxygen = 28 g
Number of moles = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass of oxygen = 16 g/mol
Now we will put the values in formula:
Number of moles = 28 g / 16 g/mol
Number of moles = 1.75 mol
So 28 g of oxygen contain 1.75 moles.
3) Find the number of moles of argon in 452 g?
Answer:
11.31 mol
Explanation:
Given data:
Mass of argon = 452 g
Number of moles = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass of argon= 39.95 g/mol
Now we will put the values in formula:
Number of moles = 452 g /39.95 g/mol
Number of moles = 11.31 mol
So 452 g of argon contain 11.31 moles.
2) What is the mass of 5.0 moles of iron?
Answer:
Mass = 279.25 g
Explanation:
Given data:
Mass of iron = ?
Number of moles of iron = 5.0 mol
Solution:
Formula:
Mass = number of moles × molar mass
Molar mass of iron = 55.85 g/mol
Now we will put the values in formula:
Mass = number of moles × molar mass
Mass = 5 mol × 55.85 g/mol
Mass = 279.25 g
4) Find the grams of 16.5 mole of hydrogen?
Answer:
Mass = 16.632 g
Explanation:
Given data:
Mass of hydrogen = ?
Number of moles of hydrogen = 16.5 mol
Solution:
Formula:
Mass = number of moles × molar mass
Molar mass of hydrogen = 1.008 g/mol
Now we will put the values in formula:
Mass = number of moles × molar mass
Mass = 16.5 × 1.008 g/mol
Mass = 16.632 g
