Answer:
A) yes
B) The average mass of 12 pennies should be expressed as
( 3.131 + 3.129 + -------- X12 ) g / 12
where X12 = is the mass of the 12th penny
Explanation:
A) I think the the Bureau of Mint changed the way it made pennies because from the experiment and observation carried out on 15 different pennies it can be seen that they had different weights and this difference is associated with the period/time of production of the different pennies,
B ) The average mass of any object should be expressed in the si unit of mass and not having ($) sign attached to the value instead it should be expressed in grams or kilograms (s.i unit of mass )
The average mass of 12 pennies should be expressed as
( 3.131 + 3.129 + -------- X12 ) g / 12
where X12 = is the mass of the 12th penny
It should be 3.36 g / min but i m not sure
Answer:
0.4
Explanation:
Given data:
Number of moles of SrCl₂ consumed = ?
Mass of ZnCl₂ produced = 54 g
Solution:
Chemical equation:
ZnSO₄ + SrCl₂ → SrSO₄ + ZnCl₂
Number of moles of ZnCl₂:
Number of moles = mass/ molar mass
Number of moles = 54 g/136.3 g/mol
Number of moles = 0.4 mol
Now we will compare the moles of ZnCl₂ with SrCl₂ from balance chemical equation.
ZnCl₂ : SrCl₂
1 : 1
0.4 : 0.4
Thus when 54 g of ZnCl₂ produced 0.4 moles of SrCl₂ react.