1. To solve this question, you need to equalize the mass of solute for both solution. The calculation would be:
mass of solute= volume*concentration
mass1=mass2
volume1 * concentration1 = volume2 * concentration2
volume1 * 0.7%= 2L *(1000ml/L) * 0.2%
volume1 = 2000ml * (0.2%/0.7%)
volume1= 571.429 ml
2. Since you already have the volume of stock needed, you just need to subtract it from the total solution volume to count the number of solvents needed.
new solution volume= stock volume + diluting solvent volume
2L * 2000ml/L = 571.429ml + diluting solvent volume
diluting solvent volume= 2000ml- 571.429 ml= 1428.571ml
Answer: 55,000
<u>Explanation:</u>
Scientific Notation: 5.5 x 10⁴
Standard form: move the decimal 4 places to the right
5 5 0 0 0 0.
= 55,000
Moles of MgS2O3 = 223/molar mass of MgS2O3
= 223/136.42
= 1.634 moles.
Hope this helps!
Molarity is the measure of a concentration of a certain chemical substance
Answer:
102 g Al₂O₃
Explanation:
To find the mass of Al₂O₃, you need to (1) convert grams Al to moles Al (via molar mass), then (2) convert moles Al to moles Al₂O₃ (via mole-to-mole ratio from reaction coefficients), and then (3) convert moles Al₂O₃ to grams Al₂O₃ (via molar mass). It is important to arrange the ratios in a way that allows for the cancellation of units. The final answer should have 3 sig figs to reflect the given values.
Molar Mass (Al): 26.98 g/mol
Molar Mass (Al₂O₃): 101.96 g/mol
4 Al + 3 O₂ ---> 2 Al₂O₃
54.0 g Al 1 mole 2 moles Al₂O₃ 101.96 g
-------------- x ----------------- x ----------------------- x ---------------- = 102 g Al₂O₃
26.98 g 4 moles Al 1 mole
