<span>the molar mass of a compound is the sum of the products of the atomic masses by the number of atoms of the element.
molar mass of Na</span>₂SO₄<span> is - 142 g/mol.
1 mol of </span>Na₂SO₄<span> has a mass of 142 g.
In 1 mol of </span>Na₂SO₄<span> the mass of Na is 23 g/mol x 2 = 46 g.
Mass of Na in 1 mol of </span>Na₂SO₄ is - 46 g
mass of Na in 0.820 mol of Na₂SO₄ - 46 g /1 mol x 0.820 mol = 37.72 g.
mass of Na is 37.72 g
Each element absorbs light at specific wavelengths unique to that atom. When astronomers look at an object's spectrum, they can determine its composition based on these wavelengths.
Not sure if this is 100% but I hope it helps.
Answer: 
Explanation:
General representation of an element is given as: 
where,
Z represents Atomic number
A represents Mass number
X represents the symbol of an element
Beta decay : In this process, a neutron gets converted into a proton and an electron releasing a beta-particle. The beta particle released carries a charge of -1 units.
The given reaction would be represented as:
Answer:
773.43 torr
Explanation:
From the question given above, the following data were obtained:
Pressure (in inHg) = 30.45 inHg
Pressure (in torr) =?
We can convert 30.45 inHg to torr by doing the following:
1 inHg = 25.4 torr
Therefore,
30.45 inHg = 30.45 inHg × 25.4 torr / 1 inHg
30.45 inhg = 773.43 torr
Thus, 30.45 inhg is equivalent to 773.43 torr
Hey I can't see the questions properly
