Answer:
0.18× 10²³ molecules
Explanation:
Given data:
Mass of copper hydroxide = 3.30 g
Number of molecules = ?
Solution:
Number of moles = mass/molar mass
Number of moles = 3.30 g/97.56 g/mol
Number of moles = 0.03 mol
Avogadro number:
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.
1 mole = 6.022 × 10²³ molecules
0.03 mol × 6.022 × 10²³ molecules / 1mol
0.18× 10²³ molecules
Answer:
The molarity of the solution is 7.4 mol/L
Explanation:
From the question above
0.400 ml of water contains 1.00 g of hydrochloride form of cocaine
Therefore 1000 ml of water will contain x g of hydrochloride form of cocaine
x = 1000 / 0.400
x = 2500 g
2500g of hydrochloride form of cocaine is present in 1000 ml of water.
Mole of hydrochloride form of cocaine = mass /molar mass of hydrochloride
Mole of hydrochloride form of cocaine = 2500/339.8
= 7.4 mol
Molarity = mol/ volume in liter (L)
molarity = 7.4 /1
Molarity = 7.4 mol/L
The answer to this would be helium
Answer:
Chitin
Explanation:
A fly's main body is made of a thorax and an abdomen. These parts are covered by a hard exoskeleton made of a bony substance called chitin.