Answer:
it's answer is lithium and boron.
Answer:
1. Energy intensity (primary energy consumption divided by GDP) for the world and various countries. The lower the value, the less energy is used to generate economic output, so lower means more efficient in a sense.
2.Lower Your Thermostat. Adopt the habit of lowering the temperature on your thermostat while away from home.
Start a Compost Pile.
Install Low-Flow Showerheads.
Seal All Windows.
Limit Space Heater Use.
Turn Off Unnecessary Water.
Replace Incandescent Bulbs.
Unplug Unused Chargers.
Answer:
pH = -log₁₀ [H⁺]
Explanation:
pH is a value in chemistry used in to measure solution trying to determine each quality, purity, risks for health of some products, etc.
As you write in the question, [H⁺] = 10^(-pH)
Using logarithm law (log (m^(p) = p log(m):
log₁₀ [H⁺] = -pH
And
<h3>pH = -log₁₀ [H⁺]</h3>
Answer:
19.4 g of alum, will be its theoretical yield
Explanation:
The reaction is:
2 Al + 2 KOH + 4 H₂SO₄ + 22H₂O → 3H₂ + 2KAl(SO₄)₂•12H₂O
Let's determine the amount of acid.
M are the moles contained in 1 L of solution or it can be mmoles that are contained in 1 mL of solution
M = mmol /mL
M . mL = mmol
We replace: 8.3 mL . 9.9 M = 82.17 mmoles
We convert to moles: 82.17 mmol . 1 mol / 1000mmol = 0.082 moles
Ratio is 4:2
4 moles of sulfuric acid can make 2 moles of alum
By the way, 0.082 moles of acid may produce ( 0.082 . 2) /4 = 0.041085 moles.
We convert moles to mass:
Molar mass of alum is: 473.52 g/mol.
0.041085 moles . 473.52 g/mol = 19.4 g