To determine the mass of xenon tetrafluoride, we need to know first the number of fluorine atoms present in <span>oxygen difluoride. We need to convert first the mass into moles then make use of the relation of the elements from the chemical formula. Then, use the avogadro's number to convert it to number of atoms. Then, we do the reverse of the steps above but this time for </span><span>xenon tetrafluoride.
25.0 g OF2 ( 1 mol / 54 g ) ( 2 mol F / 1 mol OF2 ) ( 6.022 x10^23 atoms F / 1 mol F ) ( 1 mol / 6.022x10^23 atoms) ( 1 mol XeF4 / 4 mol F ) (207.3 g / 1 mol XeF4) = 47.99 g XeF4</span>
<u>1) find molar mass of CH₄</u>

<u>2) determine moles of CH₄</u>

<u>3) multiply by avogadro's number</u>

Answer:

Explanation
Density can be found by dividing the mass by the volume.

We know the iron sheet has a mass of 28.5 grams and the volume is 3.60 milliliters.

Substitute the values into the formula.

Divide.

Let's round to the nearest thousandth.
The 6 in the ten-thousandth tells us to round the 6 to a 7.

The density of iron is about <u>7.917 grams per milliliter.</u>
D) An atom with 4 protons, 3 neutrons, and 3 electrons
Answer:
Cr(s) ⟶ Cr⁴⁺(aq) + 4e⁻
Explanation:
1. Write the skeleton half-reaction
Cr(s) ⟶ Cr⁴⁺(aq)
2. Balance charge
Add electrons to the side that needs them.
You have 4+ on the right and 0 on the left. You must add 4e⁻ to the right to balance the charge.
Cr(s) ⟶ Cr⁴⁺(aq) + 4e⁻