D) 59 (protons+neutrons=mass)
We collect gas using special apparatus because most gasses cannot be seen, hence we may find it difficult to tell if our test tube is filled, and the best method to collect gas is through water.
One of the apparatus we use in collecting gas is pneumatic trough. A pneumatic trough is a piece of laboratory apparatus used for collecting gases, such as hydrogen, oxygen and nitrogen.
<em>Assumptions we make when using the gas collection apparatus</em>
The assumption we make is on the basis of the ideal gas assumption which are:
- The gas consists of a large number of molecules, which are in random motion and obey Newton's laws of motion;
- The volume of the molecules is negligibly small compared to the volume occupied by the gas; and
- No forces act on the molecules except during elastic collisions of negligible duration.
For more information on the ideal gas assumption kindly visit
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3-25200 m
4- 0.0023 cl
5-
6- 23 mm
7-4500mm
8-450000ml
9-0.45kg
10-
Sorry I couldn’t get them all but there is most of the answers
The moles of magnesium in 1.25 x 1023 are 20.8 mol.
<u>Answer:</u>
<em>0.264 g of 
can be formed from 288 mg of 
</em>
<u>Explanation:</u>
The balanced chemical equation is
The conversions are
Mass in mg is converted to mass in g
Mass in g is converted to moles by dividing with molar mass
Moles is converted to moles by using the mole ratio of 
is 9 : 6
Moles is converted to mass by multiplying with molar mass
mass in mg > mass in g >moles > moles > mass
=0.264g (Answer)
