Chemical Equations And Mass Changes Flashcards
(12 cards)
What does the law of conservation of mass tell us?
Mass is conserved in a chemical reaction. you cannot destroy or create atoms in chemical reactions.
What does (s) mean
Solid
What does (L) mean
Liquid
What does (g) mean
Gas
What does (aq) mean
Aqueous (dissolved in water)
Is the statement true or false:
“ in a chemical reaction, the total mass of the products must equal the total mass of the reactants”
True
In chemical and word equations are the reactants found to the left of the arrow or the right of the arrow?
Left
Mass is always………….. in a chemical reaction
The same
Hydrochloric acid is formed when hydrogen chloride HCl is dissolved in water.
It’s hydrogen chloride an element, compound or mixture justify your answer
HCl is a compound because it can’t be an element because it’s made up of two elements and two different types of atoms and it can’t be a mixture because it’s written as a symbol formula as well as this it has two different elements chemically bonded together which is the definition of a compound.
Calcium carbonate has a chemical formula CaCO3; which elements does it contain an in what ratios?
Calcium, carbon and oxygen 1:1:3
Explain why masses seem to decrease
Because the gas that was weighed at the beginning as part of the reactants escaped during the experiment and can no longer be weighed.
Explain why mass seem to increase
Because the gas that was part of the experiment and formed part of the product wasn’t weighed with the reactants because it was in the gas around us. Therefore, when it was added in at the end and was able to be weighed in the mass appeared to increase.
