Answer:
Ba has the largest atom size
Answer: Thus 0.724 mol of
are needed to obtain 18.6 g of 
Explanation:
To calculate the moles :

According to stoichiometry :
2 moles of
are produced by = 1 mole of 
Thus 1.09 moles of
will be produced by =
of 
But as yield of reaction is 75.6 %, the amount of
needed is =
Thus 0.724 mol of
are needed to obtain 18.6 g of 
Astronomers can measure it by way of luminosity which is the power of a star or the amount of energy (light) the star admits from its surface. they also measure the brightness of a start as if it were to appear 32.6 light years from Earth
The balloon would be smaller and not float as well because of the low temperature. The particles in the balloon when in the car will slow down and get closer together because of the low temperature. That caused it to become more dense and smaller in size then before. When in the store, the particulars in the balloon we’re moving faster and more spread apart