Extensive property (like volume and mass), can be measured.
Explanation
There are three main branches of science: physical science, Earth science and life science. Let's talk about each branch and the areas of study within each branch. Physical science is the study of inanimate natural objects and the laws that govern them.
Answer:
Here's what I get.
Explanation:
Mg + 2HCl ⟶ MgCl₂ + H₂
According to the Law of Conservation of Mass, the total mass of the products must equal the total mass of the reactants.
However, one of the products is a gas, hydrogen. The gas escapes into the atmosphere, so you will not be weighing it at the end of the reaction.
The mass of the test tube and contents after the reaction will be less than before the reaction.
However, that doesn't violate the Law of Conservation of Mass. You just didn't measure the mass of all the products.
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 %
There are 0.000076 moles in 4.6 x 10^19 atoms.
