Transition metals are from group 3 to group 12.
Answer:
[MgSO₄] = 890 mM/L
Explanation:
In order to determine molarity we need to determine the moles of solute that are in 1L of solution.
Solute: MgSO₄ (10.7 g)
Solvent: water
Solution: 100 mL as volume. (100 mL . 1L / 1000mL) = 0.1L
We convert the solute's mass to moles → 10.7 g / 120.36 g/mol = 0.089 moles
Molarity (mol/L) → 0.089 mol/0.1L = 0.89 M
In order to calculate M to mM/L, we make this conversion:
0.89 mol . 1000 mmoles/ 1 mol = 890 mmoles
Answer:

Explanation:
<u>1. Convert Grams to Moles</u>
Use the molar mass (found on the Periodic Table) to convert from grams to moles.
Use this value as a ratio.

Multiply by the given number of grams.

Flip the ratio so the grams of boron cancel out.



<u>2. Convert Moles to Atoms</u>
We use Avogadro's Number, 6.02*10²³: the number of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case, the particles are atoms of boron.

Multiply by the number of moles we calculated.

The moles of boron cancel.


The original value of grams has 4 significant figures, so our answer should have the same. For the number we calculated, that is the thousandth place.

The 6 tells us to round the 2 to a 3.

25.00 grams of boron is equal to 1.393*10²⁴ atoms.