First find the moles
moles of the calcium= 72.8 / 40
moles of calcium in 72.8g = 1.82mol
number of atoms= moles x Avogadro constant
atoms = 1.82 x 6.02x10+23
so the number of atoms is 1.096x10+24
Answer:- solution boiling point = 102.23 degree C (102 degree C with three sig figs).
Solution:- When a non volatile solute is added to a solvent then boiling point increases. Elevation in boiling point is directly proportional to the molality of the solution.
The equation is:

where,
is the elevation in boiling point, i is the Van't hoff factor,
is the molal elevation constant and m is the molality.
Value of i is 1 as ethylene glycol is a covalent molecule that does not break to give ions.
for water is
.
We can calculate the molality from the given grams of ethylene glycol and liters of water as molality is moles of solute per kg of solvent.
Molar mass of ethylene glycol is 62 gram per mol and density of water is 1.00 kg per liter.

= 2.50 kg
Let's calculate the moles of ethylene glycol.

= 10.9 mol
molality of the solution = 
= 4.36m
Let's plug in the values in the equation we have on the top for elevation in boiling point.

= 
Boiling point of pure water is 100 degree C. So, the boiling point of the solution = 100 + 2.23 = 102.23 degree C
(If we fix the three sig figs then it could be written as 102 degree C.)
Frostbite to the skin and Severe burning to the eyes.
Answer:
709 g
Step-by-step explanation:
a) Balanced equation
Normally, we would need a balanced chemical equation.
However, we can get by with a partial equation, as log as carbon atoms are balanced.
We know we will need an equation with masses and molar masses, so let’s <em>gather all the information</em> in one place.
M_r: 30.07 236.74
C₂H₆ + … ⟶ C₂Cl₆ + …
m/g: 90.0
(i) Calculate the moles of C₂H₆
n = 90.0 g C₂H₆ × (1 mol C₂H₆ /30.07 g C₂H₆)
= 2.993 mol C₂H₆
(ii) Calculate the moles of C₂Cl₆
The molar ratio is (1 mol C₂Cl₆/1 mol C₂H₆)
n = 2.993 mol C₂H₆ × (1 mol C₂Cl₆/1 mol C₂H₆)
= 2.993 mol C₂Cl₆
(iii) Calculate the mass of C₂Cl₆
m = 2.993 mol C₂Cl₆ × (236.74 g C₂Cl₆/1 mol C₂Cl₆)
m = 709 g C₂Cl₆
The reaction produces 709 g C₂Cl₆.
Fahrenheit. 60 degrees celcius is 140 degrees fahrenheit, which is very hot.