Answer:
Aluminium atoms = 4.13 *10^22 aluminium atoms
The correct answer is E
Explanation:
Step 1: Data given
Mass of Al2O3 = 3.50 grams
Molar mass of Al2O3 = 101.96 g/mol
Number of Avogadro = 6.022 * 10^23 /mol
Step 2: Calculate moles Al2O3
Moles Al2O3 = mass Al2O3 / molar mass Al2O3
Moles Al2O3 = 3.50 grams / 101.96 g/mol
Moles Al2O3 = 0.0343 moles
Step 3: Calculate moles Aluminium
In 1 mol Al2O3 we have 2 moles Al
in 0.0343 moles Al2O3 we have 2*0.0343 = 0.0686 moles Al
Step 4: Calculate aluminium atoms
Aluminium atoms = moles aluminium * Number of Avogadro
Aluminium atoms = 0.0686 * 6.022 * 10^23
Aluminium atoms = 4.13 *10^22 aluminium atoms
The correct answer is E
The energy is transformed into kinetic energy which makes the substance to move. The law of conservation of energy which is the first law of thermodynamics states that in a closed system energy can neither be created nor destroyed but can change from one form to another
Answer:
- <u><em>The leftover reactant is the nitrogen gas, N₂.</em></u>
Explanation:
As per your description:
<u>1. Square on the left: N₂(g)</u>
- 3 units of two joint circles: this represents 3 molecules of nitrogen gas, N₂(g).
<u>2. Square on the right: H₂(g)</u>
- 3 units of two joint circles: this represents 3 molecules of hydrogen gas, H₂(g).
<u>3. Reaction</u>
If the maximum possible amount of NH₃ is formed during the reaction, you assume that the reaction goes to completion.
The chemical equation that represents the reaction is:
Which must be balanced:
That means that 1 molecule (or 1 mol) of N₂(g) reacts with 3 molecules (or 3 moles ) of H₂(g) to produce 2 molecules (or 2 moles) of NH₃(g).
Since, the squares show that there are 3 molecules of each reactant, the 3 molecules of hydrogen gas will be able to react with 1 molecule of nitrogen gas. When that happens, all the hydrogen gas is consumend and yet two molecules of nitrogen gas will remain unreacted. Hence, the nitrogen gas is the leftover reactant.
Answer:
volume in L = 0.25 L
Explanation:
Given data:
Mass of Cu(NO₃)₂ = 2.43 g
Volume of KI = ?
Solution:
Balanced chemical equation:
2Cu(NO₃)₂ + 4KI → 2CuI + I₂ + 4KNO₃
Moles of Cu(NO₃)₂:
Number of moles = mass/ molar mass
Number of moles = 2.43 g/ 187.56 g/mol
Number of moles = 0.013 mol
Now we will compare the moles of Cu(NO₃)₂ with KI.
Cu(NO₃)₂ : KI
2 : 4
0.013 : 4 × 0.013=0.052 mol
Volume of KI:
<em>Molarity = moles of solute / volume in L</em>
volume in L = moles of solute /Molarity
volume in L = 0.052 mol / 0.209 mol/L
volume in L = 0.25 L
A pure substance or a homogeneous mixture consists of a single phase. A heterogeneous mixture consists of two or more phases. When oil and water are combined, they do not mix evenly, but instead form two separate layers.
