Answer:

Explanation:
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In this case, since 12.75 g of calcium iodide has the following number of moles (molar mass = 293.89 g/mol):

In such a way, since 1 mole of calcium iodide contains 2 moles of atoms of iodine, and one mole of atoms of iodine contains 6.022x10²³ atoms (Avogadro's number), we compute the resulting atoms as shown below:

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Answer:
3.01 × 10^24 particles
Explanation:
According to Avagadro, in one mole of a substance, there are 6.02 × 10^23 atoms or particles.
Using the formula: N = n × NA
Where;
N= number of particles or atoms
n = number of moles
NA = Avagadro's constant or number
This means that for 5 moles of a substance, there will be:
5 × 6.02 × 10^23
= 30.1 × 10^23
= 3.01 × 10^24 particles
To determine what gas is this, we use Graham's Law of Effusion where it relates the rates of effusion of gases and their molar masses. We do as follows:
r1/r2 = √(M2 / M1)
Let 1 be the the unkown gas and 2 the H2 gas.
r1/r2 = 0.225
M2 = 2.02 g/mol
0.225 = √(2.02 / M1)
M1 = 39.90 g/mol
From the periodic table of elements, most likely, the gas is argon.
yes
Explanation:
the volume also decrease. as particles are removed from the space the gas is in, there is a decrease in the number of collisions.
I think is true i took the test but im not sure what i put! Correct me if wrong