Answer:
1. Rutherford did the scattering experiment and observed that some of the rays bounce back. He concluded that there is a mass in which positive charge is concentrated. This marks the discovery of nucleus.
2. J.J Thomson discovered electrons by conducting cathode ray experiment.
3. Dalton postulated that matter is made up of small particles caled atoms
Answer:
% yield = 82.5%
Explanation:
HgO + 2Cl₂ → HgCl₂ + Cl₂O
Our reactants are:
Our products are:
We do not have information about moles of reactants, but we do know the theoretical yield and the grams of product, in this case Cl₂O, we have produced.
Percent yield = (Yield produced / Theoretical yield) . 100
Theoretical yield is the mass of product which is produced by sufficent reactant. We replace data:
% yield = (0.71 g/0.86g) . 100 = 82.5%
Answer:
It would take 13 minutes.
Explanation:
The temperature decreases at a linear rate, meaning that we can describe the process by using the following formula:
Where T₂ is the final temperature, T₀ is the initial temperature; and t is the elapsed time in minutes.
We input the data given by the problem:
- 0 °C = 26 °C - 2°C/min * t
And solve for t:
Answer: 69.72 kg of cryolite will be produced.
Explanation:
The balanced chemical equation is:

To calculate the moles, we use the equation:

moles of
= 
moles of
= 
moles of
= 
As 1 mole of
reacts with 6 moles of 
166 moles of
reacts with =
moles of 
As 1 mole of
reacts with 12 moles of 
166 moles of
reacts with =
moles of 
Thus
is the limiting reagent.
As 1 mole of
produces = 2 moles of cryolite
166 moles of
reacts with =
moles of cryolite
Mass of cryolite
= 
Thus 69.72 kg of cryolite will be produced.
The answers that are correct are a, b, and d