Answer:
96 g of O
Explanation:
Mg(OH)₂ → Magnesium hydroxide
Molar mass → 24.3g/mol . 1 + 16g/mol . 2 + 1g/mol . 2 = 58.3 g/mol
We determine the moles of hydroxide → 175 g . 1mol/58.3g = 3 moles
Let's make some rule of three:
In 100 g of compound we have 54.87 g of O
In 58.3 g of compound we may have (58.3 . 54.87) / 100 = 32 g
So, 1 mol of hydroxide has 32 g of oxygen
3 moles of hyroxide may have (3 .32)/1 = 96 g of O
Answer: Thus 8.41 g was the mass of the original sample
Explanation:
To calculate the moles :
According to stoichiometry :
As 3 moles of 
are produced by = 2 moles of 
Thus 0.103 moles of are produced by =
of
Mass of 
Thus 8.41 g was the mass of the original sample.
Answer: Molar mass is the amount grams that one mole weighs.
Explanation: You need to find the molar mass of NaCl which is the same as the amu on the periodic table in grams. So it is 22.99(Na) + 35.45(Cl) = 58.44
You also know that for every mole of NaCl you have 1 mole of Na because every molecule of NaCl has 1 atom of Na.
Finally, using the periodic table, again, you see that the molar mass of Na is 22.99.
Then using stoichiometry, you can find the grams of sodium.
100(g NaCl) * 1 mol (NaCl)/58.44 g (NaCl) * 1 mol (Na)/ 1 mol (NaCl) * 22.99 (g of Na)/ 1 mol (Na)
which equals 39.339435 g of Na.
If you need to maintain significant figures the answer will be 40.
Answer:
When dealing with the force of gravity between two objects, there are only two things that are important mass, and distance. The force of gravity depends directly upon the masses of the two objects, and inversely on the square of the distance between them.
Explanation
