Answer:
13.7 moles
Explanation:
Given data:
Number of moles calcium carbonate = ?
Formula units calcium carbonate= 8.23 × 10²⁴
Solution:
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 8.23 × 10²⁴ formula units:
one mole = 6.022 × 10²³ formula units
8.23 × 10²⁴ formula units × 1 mole /6.022 × 10²³ formula units
13.7 moles
I think that the answer is B, but I may be wrong...
Answer:
1.602 L (or) 1602 mL
Explanation:
Molarity is the amount of solute dissolved per unit volume of solution. It is expressed as,
Molarity = Moles / Volume of Solution ----- (1)
Rearranging above equation for volume,
Volume of solution = Moles / Molarity -------(2)
Data Given;
Molarity = 0.00813 mol.L⁻¹
Mass = 1.55 g
First calculate Moles for given mass as,
Moles = Mass / M.mass
Moles = 1.55 g / 119.002 g.mol⁻¹
Moles = 0.0130 mol
Now, putting value of Moles and Molarity in eq. 2,
Volume of solution = 0.0130 mol / 0.00813 mol.L⁻¹
Volume of solution = 1.60 L
or,
Volume of solution = 1602 mL
Every redox reaction consists of two parts, the oxidation and the reduction. Each one separately is called a half - reaction. During the redox reaction there is a transfer of electrons from the substance being oxidized to the substance being reduced.
