1 mole of a pure substance has a mass equal to its molecular mass expressed in grams.
This is known as the molar mass, M, and has the units g mol-1
So 2 moles of a substance would have a mass = 2 x molar mass
3 moles of a substance would have a mass = 3 x molar mass etc
This leads to the formula: mass = moles x molar mass
If we let:
m = mass of substance in grams,
n = moles of pure substance,
M = molar mass of the pure substance in g mol-1
we can write the equation: m = n x M
This equation can be rearranged to give the following:
n = m ÷ M (moles = mass ÷ molar mass)
M = m ÷ n (molar mass = mass ÷ moles)
Answer:
Hydrogen Gas
Explanation:
The hydrogen gas now in the test tube is flammable. So when I hold the tube over the flame, the hydrogen gas ignites and creates a popping sound. It is like a tiny bomb or fireworks.
Hope this helped! :)
<u>Ans 1:</u>
Ammonia is not collected over water since it is highly soluble in water
<u>Ans 2:</u>
Ammonia gas is lighter than air and hence collected by the downward displacement of air.
<u>Ans 3:</u>
The carbon dioxide is very cold as it comes out of the extinguisher, so it cools the fuel as well.
<u>Ans 4:</u>
H₂SO₄ is not used in the preparation of carbon dioxide Because the calcium sulphate formed is insoluble in water. So, CO₂ will not form.
<u>Ans 5:</u>
The opening of hard glass test tube is slanted down during laboratory preparation of ammonia gas because Ammonia gas is not collected in the gas jar by upward displacement of air because it is lighter than air
<u>Ans 6:</u>
Magnesium is reactive enough to be combusted and oxidized in a reaction with carbon dioxide:
The magnesium strip burns brightly in the air, but continues to burn in the carbon dioxide environment
<u>-</u><u>TheUnkownScientist</u>
Answer: The answer is D.
Explanation: The warm water will cause the sugar to dissolve quicker.
I can help you but what is the question here?
