In chemistry, if you want to express the amount of a substance out of the total amount, you express it in concentration. There are numerous units of measurement: molarity, molality, normality, mass percentages, volume percentage, or a mix of both. For this problem, the unit used for concentration is in mass percentages. The formula would be
Percentage Concentration = [(Actual Amount of Substance)/(Total amount of all substances)] * 100
Since we are given with the total mass of all the substances in the ocean and the percentage concentration, the only missing information is the actual amount of Na+ in the ocean. Substituting the values:
1.076 = (Amount of Na+ /1.8×10²¹ kg)*100
Amount of Na+ = 1.9368×10¹⁹ kg
Answer:
2 molecules of water represents 3.32 x 10^-24 moles of water.
Explanation:
To find the solution to this problem, you have to use the concept of Avogadro´s number, that is in 1 mol of any element o compound there are 6.022 x 10^23 molecules. Then,
1 mol H2O ------------- 6.022 x 10^23 molecules
x= 3.32 x 10^-24 ---- 2 molecules.
2 molecules of water represents 3.32 x 10^-24 moles of water.
Answer: I'm sure it is c
Explanation: that's my answer
Answer: 
Explanation:
Multiply by t on both sides.
Now divide by I to isolate t.
The complete balanced chemical reaction is:
2 AgNO3 + Na2S --> 2 NaNO3 + Ag2S
First let us calculate the number of moles of AgNO3.
moles AgNO3 = 0.315 M * 0.035 L
moles AgNO3 = 0.011025 mol
From the reaction, 1 mole of Na2S is needed for every 2
moles of AgNO3 hence:
moles Na2S required = 0.011025 mol AgNO3 * (1 mol Na2S / 2
mol AgNO3)
moles Na2S required = 5.5125 x 10^-3 mol
Therefore volume required is:
volume Na2S = 5.5125 x 10^-3 mol / 0.260 M
<span>volume Na2S = 0.0212 L = 21.2 mL</span>
