That is not a question/problem and makes no sense whatsoever
When magnesium is burned, it reacts with oxygen in air not with the fire. The fire is the energy needed for the reaction to happen. Magnesium reacts with oxygen forming magnesium oxide. The light emitted from the reaction is because the reaction produced a lot of heat.
Answer:
38.541 × 10¹⁹ formula units
Explanation:
Given data:
Mass of chromium sulfate = 0.25 g
Formula units in 0.25 g = ?
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 formula units of water
Number of moles of chromium sulfate = Mass / molar mass
Number of moles of chromium sulfate = 0.25 g/ 392.16 g/ mol
Number of moles of chromium sulfate = 6.4 × 10⁻⁴ moles
Number of formula units:
1 mole = 6.022 × 10²³ formula units
6.4 × 10⁻⁴ moles × 6.022 × 10²³ formula units / 1 mol
38.541 × 10¹⁹ formula units
Copper (I) oxidation state is 1 Cu2So4
copper (II) oxidation state is +2 CuSo4
copper (i) also give up one electron so you need two of them to react with the sulfate ion (which has charge of -2)
and also all metallic ions have an multiple oxidation levels corresponding to the number of electrons they can exchange or loose
Hope this helps
