Answer:
There are 0.00523 moles of oxygen in 0.150 grams of calcium sulfate crystal.
Explanation:
Mass of calcium sulfate crystal = m = 0.150 g
Molar mass of calcium sulfate crystal = M = 172 g/mol
Moles of magnesium nitrate = n


1 mole of calcium sulfate crystal has 6 moles of oxygen atoms. Then 0.004446 moles calcium sulfate crystal will have :

There are 0.00523 moles of oxygen in 0.150 grams of calcium sulfate crystal.
Answer:
, 
Explanation:
The change in energy is given by the change in gravitational potential energy:



The average rate of change in terms of time is approximately this:



add up the mass of protons and neutrons
Because the copper roofs, have been outside for a while and oxidization has occurred.
When metals become oxidized they rust, but when copper becomes oxidized, it turns greenish.
So copper roofs oxidize and turn green from being outside and a copper square doesn’t if it’s inside.