1.5 % is the percent yield in the reaction.
Explanation:
Given that:
original mass of the sample used in reaction = 1.897 grams
product formed after decomposition = 1.071 grams
The reaction for the decomposition:
Mg(HCO3)2 (s) ⇒ CO2 (g) + H2O (g) + MgCO2 (s)
It says that 1 mole of Mg(HCO3)2 yielded 1 mole of MgCO2 on decomposition
68.31 grams/mole or 68.31 grams of MgCO2 is formed
percent yield =
x 100
putting the values in the equation:
percent yield = 
= 0.015 x100
PERCENT YIELD = 1.5 %
Answer:

Explanation:
Hello,
In this case, the Boyle's is mathematically defined via:

Which stands for an inversely proportional relationship between volume and pressure, it means the higher the volume the lower the pressure and vice versa. In such a way, since the volume is decreased to one quarter, we can write:

We can compute the new pressure:

Which means the pressure is increased by a factor of four.
Regards.
Formula: NA2S2O3. Valency: 2
it will produce aluminum hydride and lithium chloride.
First, you need to count copper mass in alloy.
Second, you have to make an equation an find x ( the copper mass must be added). The answer is: 13,5g pure copper