That is, the molar mass of a substance is the mass (in grams per mole) of 6.022 × 1023 atoms, molecules, or formula units of that substance. In each case, the number of grams in 1 mol is the same as the number of atomic mass units that describe the atomic mass, the molecular mass, or the formula mass, respectively.

3 0

2 years ago

How many moles are found in a 100.0-g sample of CuF2?

ivolga24 [154]

To determine the amount of a substance in units of moles from units of grams, we need to determine the molar mass of the substance. The molar mass is the mass of a given chemical element or chemical compound (g) divided by the amount of substance (mol). For CuF2, the molar mass 101.543 g/mol. We calculate as follows:

100.0 g CuF2 ( 1 mol / 101.543 g) = 0.98 mol CuF2

6 0

2 years ago

To a 25.00 mL volumetric flask, a lab technician adds a 0.150 g sample of a weak monoprotic acid, HA , and dilutes to the mark w

Elis [28]

Answer: The number of moles of weak acid is $4.24\times 10^{-3}$ moles.

Explanation:

To calculate the moles of KOH, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}\text{Volume of solution (in L)}}$

We are given:

Volume of solution = 43.81 mL = 0.04381 L (Conversion factor: 1L = 1000 mL)

Molarity of the solution = 0.0969 moles/ L

Putting values in above equation, we get:

$0.0969mol/L=\frac{\text{Moles of KOH}}{0.04381}\\\\\text{Moles of KOH}=4.24\times 10^{-3}mol$

The chemical reaction of weak monoprotic acid and KOH follows the equation:

$HA+KOH\rightarrow KA+H_2O$

By Stoichiometry of the reaction:

1 mole of KOH reacts with 1 mole of weak monoprotic acid.

So, $4.24\times 10^{-3}mol$ of KOH will react with = $\frac{1}{1}\times 4.24\times 10^{-3}=4.24\times 10^{-3}mol$ of weak monoprotic acid.

Hence, the number of moles of weak acid is $4.24\times 10^{-3}$ moles.

6 0

3 years ago

How to differentiate between so3 and so4?

makvit [3.9K]

Answer:

The difference between sulfate and sulfite is, Sulfate (SO4) has 1 atom of Sulphur and 4 atoms of Oxygen. sulfite (SO3) has 1 atom of sulfur and 3 atoms of Oxygen.

Explanation:

7 0

2 years ago