The percentage adds up to 100%.
<h3>Percentages</h3>
Mass of mixture = mass of container+mixture - mass of container = 56.779 - 54.558 = 2.221 g
CuCO3 is insoluble in water. Thus:
Mass of CuCO3 = mass of beaker and residue - mass of beaker = 78.875 - 77.575 = 1.300 g
Mass of NaCl = mass of mixture - mass of CuCO3 = 2.221 - 1.300 = 0.921 g
%NaCl (w/w) = weight of NaCl/weight of mixture = 10.921/2.221 = 41.468%
% (w/w) CuCO3 = weight of CuCO3/weight of mixture = 1.300/2.221 = 58.532%
Addition of percentages = 41.468 + 58.532 = 100%
More on percentages can be found here: brainly.com/question/24159063
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True
Pressure is the force per unit area on an object. The force in the case of air pressure is the weight of the air molecules; therefore, the air pressure is essentially due to gravity pulling down air molecules.
According to the law of conservation of Mass:
In a chemical reaction mass can neither be created nor be destroyed
So, we can say that: Mass of A + Mass of B = Mass of C
In the given reaction,
One of the reactants weigh 5 grams and another one weighs x grams
The mass of the product of this reaction is 9 grams
<u>Mass of reactant B:</u>
Mass of A + Mass of B = Mass of C
5 + x = 9
x = 4 grams
A(n) Acute exposure is a short term or brief exposure that may create an immediate health hazard. Answer: A)
B, the height above or below sea level
