Answer:
Explanation:
Atom X,
Neutron num = 4, Mass num = 7
Therefore, proton number = Mass num - Neutron num
= 7 - 4
= 3
Atom Y,
Neutron num = 5, Mass num = 9
Therefore, proton number = Mass num - Neutron num
= 9 - 5
= 4
1) False. Atom X belongs to group 3 while atom Y belongs to group 4
2) False. Atom X is in a column on the left of Atom Y
3) True. Atom X and atom Y belong to the same period two on the periodic table
4) Fasle. Atom X and Y are not isotopes because they do not have the same atomic number.
Isotopy is a phenomenon whereby atom of same element have same atomic number but different mass number
The second one is more concentrated as they both times with the same thing but the second one (1.5) is bigger
An exothermic reaction is a type of reaction that dissipates heat as the reaction proceeds. This would mean that in a closed system, when a reaction proceeds and is endothermic, the temperature of the solution or the system would increase so as to maintain the equilibrium with the whole system.
Aluminum is an element. If there's nothing else in the foil
besides aluminum, then the foil is entirely an element.
The rate of disappearance of chlorine gas : 0.2 mol/dm³
<h3>Further explanation</h3>
The reaction rate (v) shows the change in the concentration of the substance (changes in addition to concentrations for reaction products or changes in concentration reduction for reactants) per unit time.
For reaction :

The rate reaction :
![\tt -\dfrac{1}{a}\dfrac{d[-A]}{dt}= -\dfrac{1}{b}\dfrac{d[-B]}{dt}=\dfrac{1}{c}\dfrac{d[C]}{dt}=\dfrac{1}{d}\dfrac{d[D]}{dt}](https://tex.z-dn.net/?f=%5Ctt%20-%5Cdfrac%7B1%7D%7Ba%7D%5Cdfrac%7Bd%5B-A%5D%7D%7Bdt%7D%3D%20-%5Cdfrac%7B1%7D%7Bb%7D%5Cdfrac%7Bd%5B-B%5D%7D%7Bdt%7D%3D%5Cdfrac%7B1%7D%7Bc%7D%5Cdfrac%7Bd%5BC%5D%7D%7Bdt%7D%3D%5Cdfrac%7B1%7D%7Bd%7D%5Cdfrac%7Bd%5BD%5D%7D%7Bdt%7D)
Reaction for formation CCl₄ :
<em>CH₄+4Cl₂⇒CCl₄+4HCl</em>
<em />
From equation, rate of reaction = rate of formation CCl₄ = 0.05 mol/dm³
Rate of formation of CCl₄ = reaction rate x coefficient of CCCl₄
0.05 mol/dm³ = reaction rate x 1⇒reaction rate = 0.05 mol/dm³
The rate of disappearance of chlorine gas (Cl₂) :
Rate of disappearance of Cl₂ = reaction rate x coefficient of Cl₂
Rate of disappearance of Cl₂ = 0.05 x 4 = 0.2 mol/dm³