Answer: Mass is 2,37 kg
Explanation: Weight G = mg, and g = 9.81 m/s² on Earth.
m = W/g = 23.2 N / 9.81 m/s²
Answer : The percent by mass of the solution is 7.81 %
Explanation : Given,
Mass of NaCl = 8.75 g
Mass of solution = 112.0 g
Now we have to determine the percent by mass of the solution.

Putting values in above equation, we get:

Therefore, the percent by mass of the solution is 7.81 %
Answer:

Explanation:
We are asked to find how many moles are in 4.8 × 10²³ fluorine atoms. We convert atoms to moles using Avogadro's Number or 6.022 × 10²³. This is the number of particles (atoms, molecules, formula units, etc.) in 1 mole of a substance. In this case, the particles are atoms of fluorine.
We will convert using dimensional analysis and set up a ratio using Avogadro's Number.

We are converting 4.8 × 10²³ fluorine atoms to moles, so we multiply the ratio by this number.

Flip the ratio so the units of atoms of fluorine cancel each other out.


Condense into 1 fraction.

Divide.

The original measurement of atoms has 2 significant figures, so our answer must have the same. For the number we found, that is the hundredths place. The 7 in the thousandths tells us to round the 9 in the hundredths place up to a 0. Then, we also have to round the 7 in the tenths place up to an 8.

4.8 × 10²³ fluorine atoms are equal to <u>0.80 moles of fluorine.</u>
Answer:
1.76
Explanation:
There is some info missing. I think this is the original question.
<em>A chemist dissolves 660.mg of pure hydroiodic acid in enough water to make up 300.mL of solution. Calculate the pH of the solution. Be sure your answer has the correct number of significant digits.</em>
<em />
Step 1: Calculate the molarity of HI(aq)
M = mass of solute / molar mass of solute × liters of solution
M = 0.660 g / 127.91 g/mol × 0.300 L
M = 0.0172 M
Step 2: Write the acid dissociation reaction
HI(aq) ⇄ H⁺(aq) + I⁻(aq)
HI is a strong acid, so [H⁺] = 0.0172 M
Step 3: Calculate the pH
pH = -log [H⁺]
pH = -log 0.0172
pH = 1.76