Fe: 2 x 55.845 = 111.69
O: 3 x 15.9994= 47.9982
111.69 + 47.9982 = 159.69 g/mol
The electron microscope uses a beam of electrons and their wave-like characteristics to magnify an object's image, unlike the optical microscope that uses visible light to magnify images.
Answer: option C, a mixture
Explanation:
Crude oil is a mixture of hydrocarbons and different organic materials. It is refined into useful materials like petrol,diesel and various petrochemicals.
<u>Answer: </u>The mass of water produced is 44.28 g
<u>Explanation:</u>
We are given:
Volume of oxygen gas = 27.50 L
At STP conditions:
22.4 L of volume is occupied by 1 mole of a substance
27.50 L of oxygen gas will be occupied by = 
The chemical equation for the formation of water follows:

By the stoichiometry of the reaction:
If 1 mole of oxygen gas produces 2 moles of water
So, 1.23 moles of oxygen gas will produce =
of water
The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:
......(1)
Molar mass of water = 18 g/mol
Plugging values in equation 1:

Hence, the mass of water produced is 44.28 g