Answer: D. All of the above describe a mole
Explanation:
Mole is the unit for amount of substance.<em> </em>It is used for describing large number of particles.
According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number of particles.
For example: 1 mole of Na atom will weigh 23 grams and contains atoms.
Thus all the above describes a mole.
Answer:
- What is the limiting reactant?: HCl is the limitng reactant.
- How many moles of H₂ are formed?: 6.5 moles of H₂ are formed.
Explanation:
Part A: <em>what is the limiting reactant?</em>
1) <u>Balanced chemical equation</u>: given
- 2Al + 6HCl → 2AlCl₃ + 3H₂
2)<em> </em><u>Stoichiometric mole ratio:</u>
Use the coefficients of the balanced equation:
- 2 mol Al : 6 mol HCl : 2 mol AlCl₃ : 3H₂
3) <u>Compare the stoichiometric mole ratio of the reactants with their actual ratio</u>:
- Theoretical ratio: 2 mol Al / 6 mol HCl ≈ 0.33 mol Al / mol HCl
- Actual ratio: 6.0 mol Al / 13 mol Cl ≈ 0.46 mol Al / mol Cl
Since the actual ratio indicates that there is a greater number of moles of Al (0.46) per mol of Cl than what is required by the stoichiometric ratio(0.33), Al is in excess and HCl is the limiting reactant.
Answer: the limiting reactant is HCl.
Part B. <em>How many moles of H₂ are formed?</em>
3. <u>Determine how many moles of H₂ can be formed</u>
- Theoretical ratio using limiting reactant:
6 mol HCl / 3 mol H₂ = 13 mol HCl / x
⇒ x = 13 mol HCl × 3 mol H₂ / 6 mol HCl = 6.5 mol H₂.
The answer must be reported with two significant digits, such as the data are given.
Answer: 6.5 moles of H₂ are formed
Answer:
Explanation:
The answer is B heavy nucleus splits into two smaller nuclei
The correct answer is (C), this is because (A) talks about producing energy as of where fat is a form of storing energy. (B) is talking about a cell that controls its surroundings which, as we know, is not the job of fat. That leaves (D) to rule out as it is a textbook definition of an enzyme.
physical
It can be chemical but it's usually physical as the molecular structure doesn't change