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Greeley [361]
3 years ago
8

15 POINTS RIGHT NOW!!!!

Chemistry
2 answers:
Anettt [7]3 years ago
5 0

Answer:

It is valid because his experiment had clear variables.

Explanation:

He had clear variables and did everyhting the same for both plants, even though he had calcium in one and not in the other, which gives him a true and good result.

tensa zangetsu [6.8K]3 years ago
3 0

Answer:

<h2>It is invalid because his sample size is small Option B</h2>

Explanation:

got it right on the test have a great day :3

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if Fe(NO3)3 is dissolved in enough water to make exactly 323 ml of solution, what is the molar concentartion of nitrate ion g
Ilya [14]

The given question is incomplete. the complete question is : If 5.15 gFe(NO_3)_3 is dissolved in enough water to make exactly 323 ml of solution, what is the molar concentartion of nitrate ion.

Answer:  The molar concentartion of nitrate ion is 0.195.

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

Given : 5.15 g of Fe(NO_3)_3 is dissolved

Volume of solution = 323 ml

Molarity=\frac{n\times 1000}{V_s}

where,

n= moles of solute

Moles=\frac{\text{Given mass}}{\text{Molar mass}}=\frac{5.15g}{242g/mol}=0.021moles  

V_s = volume of solution = 323 ml

Molarity=\frac{0.021\times 1000}{323}=0.065M

As 1 M of Fe(NO_3)_3 gives 3 M of NO_3^- ions.

Thus 0.065 M of Fe(NO_3)_3 gives  = \frac{3}{1}\times 0.065=0.195M of NO_3^- ions.

The molar concentartion of nitrate ion is 0.195.

4 0
3 years ago
Which of the following chemical equations is correctly balanced?
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The correct answer is B.
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3 years ago
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To break the oxygen-oxygen bonds in a single O2 molecule, 1 × 10–18 J of energy is required. Which of the following wavelengths
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E = hc/(lamda)

The lamda symbol is wavelength, which this site does not have. I can represent it with an "x" instead.

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The ratio of the mass of a proton to the mass of an electron is

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Distance divided by time
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