the answer is true the first one
Answer:
Convection occurs when particles with a lot of heat energy in a liquid or gas move and take the place of particles with less heat energy. Heat energy is transferred from hot places to cooler places by convection. Liquids and gases expand when they are heated. ... As a result, the particles take up more volume.
Answer:
Explanation:
<u>1. Molecular chemical equation:</u>
- 2 KClO₃(s) → 2 KCl(s) + 3 O₂(g)
<u>2. Mole ratios:</u>
- 2 mol KClO₃ : 2 mol KCl : 3 mol O₂
<u>3. Number of moles of KClO₃</u>
- Number of moles = mass in grams / molar mass
- Molar mass of KClO₃ = 122.55 g/mol
- Number of moles of KClO₃ = 54.3 g / 122.5 g/mol ≈ 0.44308 mol
<u>3. Number of moles of O₂</u>
As per the theoretical mole ratio 2 mol of KClO₃ produce 3 mol of O₂, then set up a proportion to determine how many moles of O₂ will be produced from 0.44038 mol of KClO₃.
- 3 mol O₂ / 2 mol KClO₃ = x / 0.44038 mol KClO₃
- x = (3 / 2) × 0.44308 mol O₂ = 0.6646 mol O₂
Round to 3 significant figures: 0.665 mol of O₂ ← answer
Answer:
The volume of hydrogen gas produced at STP is 4.90 liters.
Explanation:
Moles of aluminium =
According to reaction , 2 moles of aluminium gives 3 moles of hydrogen gas.
Then 0.1333 moles of aluminium will give:
of hydrogen gas
Volume of 0.2 moles of hydrogen gas at STP = V
Temperature at STP = T = 298.15 K
Pressure at STP = P = 1 atm
n = 0.2 mol
PV = nRT (Ideal gas equation)
The volume of hydrogen gas produced at STP is 4.90 liters.
Answer:
R = 40 ohms
Explanation:
Given that,
The voltage of outlet, V = 120 V
Current flowing through the device, I = 3 A
We need to find the Resistance rating of the power cord. Let the resistance is R. We know that,
Ohm's law, V = IR
Put all the values,
So, the resistance rating of the power cord is equal to 40 ohms.
