WorksheetsValence Electrons & Evidence of Chemical Reaction
Total questions: 15
Worksheet time: 24mins
You know that a chemical reaction is occurring here because you see __________________ . (Pick 3)
purple color
smoke
ice formation
fire
a yellow precipitate
You know that a chemical reaction is occurring here because you see __________________ . (Pick 3)
purple color
smoke
ice formation
fire
a yellow precipitate
In this chemical reaction, what was the first evidence that you saw?
Production of fire
Production of light
Production of purple smoke
Production of white powder
The result of the experiment between Iodine and Aluminum was the production of __________________.
clear liquid.
a white powder.
yellow precipitate.
bubbles.
When zinc reacted with hydrochloric acid, what was the result of this reaction?
a white powder
a blue liquid
a brown precipitate
a gas
We know that there was a chemical reaction occurring when 2 clear liquids were mixed together. That is because we show the production of a _____________.
solid.
precipitate.
gas.
A precipitate is a ___________ that forms when 2 liquids react together.
solid
liquid
gas
plasma
Reactants are the chemicals that are present at the beginning of an experiment. Reactants react together to make the product.
We can know that a chemical reaction is occurring when we see ______.
that the product looks just like the reactants.
nothing new.
that the product looks different from the reactants.
Which of the following is evidence of a chemical reaction?
Tearing paper.
Change in color.
Production of a gas.
Change in temperature.
Production of a precipitate.
Valence electrons are in the...
Innermost energy level of the atom.
Middle energy level of the atom.
Outermost energy level of the atom.
energy levels of the atom.
How many valence electrons does carbon have?
4
5
6
7
