Answer:
those have symbols for their Latin or Greek name
Explanation:
hope it helps
A physical change<span> in a substance doesn't </span>change<span> what the substance is. In a </span>chemical change<span> where there is a </span>chemical reaction<span>, a new substance is formed and energy is either given off or absorbed.</span>
X

H has a positive 1 charge. This means that having 3H = +3<span>. This is a neutral compound so x= -3 because X+3H= 0
Y</span>

is also neutral so 2X+Y= 0
we know X=-3 So, 2(-3)+Y=0
-6+y=0
Y=+6 charge
Answer: The valency of X is -3.
The valency of Y is 6
It was the element of aluminium where they predict their properties <span />
Answer:
7.81 moles
Explanation:
To solve this problem, let us generate an expression involving volume and number of mole of the gas since the pressure and temperature of the gas are constant.
From ideal gas equation:
PV = nRT
Divide both side by P
V= nRT/P
Divide both side by n
V/n = RT/P
Since RT/P are constant, then:
V1/n1 = V2/n2
Data obtained from the question include:
V1 = 4.11
n1 = 2.51 moles
V2 = 16.9L
n2 =?
Using the above equation i.e V1/n1 = V2/n2, the final number of the gas can be obtained as illustrated below:
4.11/2.51 = 16.9/n2
Cross multiply to express in linear form
4.11 x n2 = 2.51 x 16.9
Divide both side by 4.11
n2 = (2.51 x 16.9) / 4.11
n2 = 10.32moles
Now, to obtain the number of mole of the gas added, we'll subtract the initial mole from the final mole i.e
n2 — n1
Number of mole added = n2 — n1
10.32 — 2.51 = 7.81 moles
Therefore, 7.81 moles of the gas was added to the container