Answer:
1. Percentage by weight = 0.5023 = 50.23 %
2. molar fraction =0.153
Explanation:
We know that
Molar mass of HClO4 = 100.46 g/mol
So the mass of 5 Moles= 5 x 100.46
Mass (m)= 5 x 100.46 = 502.3 g
Lets assume that aqueous solution of HClO4 and the density of solution is equal to density of water.
Given that concentration HClO4 is 5 M it means that it have 5 moles of HClO4 in 1000 ml.
We know that
Mass = density x volume
Mass of 1000 ml solution = 1 x 1000 =1000 ( density = 1 gm/ml)
m'=1000 g
1.
Percentage by weight = 502.3 /1000
Percentage by weight = 0.5023 = 50.23 %
2.
We know that
molar mass of water = 18 g/mol
mass of water in 1000 ml = 1000 - 502.3 g=497.9 g
So moles of water = 497.7 /18 mole
moles of water = 27.65 moles
So molar fraction = 5/(5+27.65)
molar fraction =0.153
Given what we know, we can confirm that since Mr. Summers has to test a hypothesis, his next step should be to design an experiment.
<h3>Why design an Experiment?</h3>
- The next step is to design an experiment.
- This is because Mr. Summers has already made an observation and created a problem.
- He must now gather data to be analyzed.
- In order to do this, he must first design and perform an experiment.
Therefore, we can confirm that Mr. Summers must design an experiment given that this is the best way to gather data in order to be analyzed in the future and draw a valid conclusion.
To learn more about Hypothesis visit:
brainly.com/question/2695653?referrer=searchResults
Rutherford was one of the early scientists who worked on the atomic model. Before his discovery of the nucleus, the widely accepted theory was J.J Thomson's Plum Pudding Model. In this model, all the protons, electrons and neutrons are in the nucleus. But the electrons are more in number such that the electrons act as the 'pudding' and the proton and nucleus the 'plum'. This was Rutherford's hypothesis in his gold foil experiment. In order to test the Plum Pudding model, he hypothesized that when a beam of light is aimed at the atom, it would not diffract because the charges in the nucleus are well-distributed. However, his experiment disproved Thomson's model. Some light indeed passed through but a few was diffracted back to the source. He concluded that this was because there is a dense mass inside the atom called nucleus. Thus, from there on, he proposed the model that the electrons are orbiting around the nucleus.
Answer:
the Mercury planet is likely to have life but the earth as a lot of oxygen
Answer:
Explanation:
Your strategy here will be to
use the chemical formula of carbon dioxide to find the number of molecules of
CO
2
that would contain that many atoms of oxygen
use Avogadro's constant to convert the number of molecules to moles of carbon dioxide
use the molar mass of carbon dioxide to convert the moles to grams
So, you know that one molecule of carbon dioxide contains
one atom of carbon,
1
×
C
two atoms of oxygen,
2
×
O
This means that the given number of atoms of oxygen would correspond to
4.8
⋅
10
22
atoms O
⋅
1 molecule CO
2
2
atoms O
=
2.4
⋅
10
22
molecules CO
2
Now, one mole of any molecular substance contains exactly
6.022
⋅
10
22
molecules of that substance -- this is known as Avogadro's constant.
In your case, the sample of carbon dioxide molecules contains
2.4
⋅
10
22
molecules CO
2
⋅
1 mole CO
2
6.022
⋅
10
23
molecules CO
2
=
0.03985 moles CO
2
Finally, carbon dioxide has a molar mass of
44.01 g mol
−
1
, which means that your sample will have a mass of
0.03985
moles CO
2
⋅
44.01 g
1
mole CO
2
=
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
∣
∣
a
a
1.8 g
a
a
∣
∣
−−−−−−−−−
The answer is rounded to two sig figs, the number of sig figs you have for the number of atoms of oxygen present in the sample.
