How many grams of KCl are needed to prepare 0.750 L of a 1.50 M solution in water?

a. 83.9
b. 0.500
c. 1.13
d. 2.00

Option A) 83.9g

Explanation:

KCl is the chemical formula of potassium chloride.

Given that,

Amount of moles of KCl (n) = ?

Volume of KCl solution (v) = 0.75L

Concentration of KCl solution (c) = 1.5M

Since concentration (c) is obtained by dividing the amount of solute dissolved by the volume of solvent, hence

c = n / v

make n the subject formula

n = c x v

n = 1.5M x 0.75L

n = 1.125 mole

Now given that,

Amount of moles of KCl (n) = 1.125

Mass of KCl in grams = ?

For molar mass of KCl, use the molar masses of:

Potassium, K = 39g;

Chlorine,Cl = 35.5g

KCl = (39g + 35.5g)

= 74.5g/mol

Since, amount of moles = mass in grams / molar mass

1.125 mole = m / 74.5g/mol

m = 1.125 mole x 74.5g/mol

m = 83.81g

Thus, 83.9 grams of KCl are needed to prepare 0.750 L of a 1.50 M solution in water

i look it up online and i'll tell you

the leaf is an organ of a typical plant, and the main functions are to complete photosynthesis and allow the plant to exchange gas, just like how we have the respiratory system. leaves have the stomata, which collects maintains co2 and o2 levels. this is necessary for cell metabolism. the leaf also collects sunlight using chloroplasts. succinctly, leaves own a pivotal role in sustaining plant life.