Answer:
deep blue solution of tetramminecopper [Cu(NH3)4]2+ complex ion.
Explanation:
Atomic mass W = 183.84 u.m.a
183.84 g ----------- 6.02x10²⁴ atoms
?? g ---------------- 2.1x10²⁴ atoms
2.1x10²⁴ x 183.84 / 6.02x10²⁴ =
3.860x10²⁶ / 6.02x10²⁴ = 641.30 g
hope this helps!
Answer:
Explanation:
<u>1) Convert the mass of water into number of moles</u>
- Molar mass of water: 18.015 g/mol
- Number of moles, n = mass in grams / molar mass
n = 255 g / 18.015 g/mol = 14.15 mol
<u>2) Use the formula E = n × ΔH vap</u>
This is, you have to multiply the molar ΔH vaporization by the number of moles to find the total energy to boil the given amount of water.
- E = 14.15 mol × 40,650 J/mol = 575,395.5 J
<u>3) Round to the correct number of significant figures.</u>
The mass of water is the measurement with the least number of significant figures (3), so you must report the answer with 3 significant figures,
A is incorrect because Mg has a 2+ charge, while SO4 has a 2- charge, if there is 2 Mg and 3 SO4 then the formula will not add to 0 meaning neutral