WorksheetsUnit 3a Review
Total questions: 35
Worksheet time: 32mins
A substance that is formed as the result of a chemical reaction is a __________________
Product
Reactant
Starters
Enders
Which of the following is an example of a chemical change?
water freezes to form ice
sugar dissolves in water
gasoline burns in a car engine
a piece of metal expands when it is heated
A change in the shape of an object is an example of _________________.
a chemical change
energy
an endothermic change
a physical change
Which one shows that a chemical reaction has occurred?
dissolving
melting
formation of a gas
bending
A chemical change is different than a physical change because in a chemical change
chemicals are used
molecules do not physically touch
a new substance is formed and in a physical no new substance is formed
the change can be seen but in a physical change it cannot
Which of the following 2 are chemical reactions?
sugar dissolving in water
water turning into steam
burning wood
mixing baking soda and vinegar
tearing paper
Which of the following is a common sign that a chemical change has occurred?
A chemical has turned a different color, bubbled, and/or changed temperature.
A chemical has changed to a different state of matter, such as a liquid to a solid.
A chemical has changed size.
A chemical has become a different shape.
Look at the chemical equation.
How many atoms of mercury (Hg) are in the reactants?
(a)
Look at the chemical equation.
How many atoms of oxygen (O) are in the reactants?
(a)
Look at the chemical equation.
How many atoms of nitrogen (N) are in the reactants?
(a)
Look at the chemical equation.
How many atoms of carbon (C) are in the reactants?
(a)
The smallest particle of an element; made of electrons, protons, and neutrons
Atoms
Elements
Molecules
Products
The simplest unit of a chemical compound that can exist; formed when two or more atoms join together chemically
Atom
Compound
Molecule
This change is a
chemical reaction
physical change
musical change
all answers are correct
Which is the correct description of photosynthesis
Photosynthesis is a chemical reaction because the atoms of the molecules get rearranged to form new molecules
Photosynthesis is a chemical reaction because the molecules stay the same before and after the change
Photosynthesis is a physical change because nature makes it happen
Photosynthesis is a physical change because the atoms stay the same
The simplest natural substance is called a(n)
Element
Compound
Mixture
Solution
Two or more elements chemically combined together are called a
Element
Compound
Mixture
Solution
H2O is an example of
Compound
Element
What is the proton?
a negatively charged particle that orbits the nucleus
a neutral particle found in the nucleus
a positively charged particle found in the nucleus
a neutral particle that orbits the nucleus
What is the electron?
a negatively charged particle that orbits the nucleus
a neutral particle found in the nucleus
a positively charged particle found in the nucleus
a neutral particle that orbits the nucleus
What is the neutron?
a negatively charged particle that orbits the nucleus
a neutral particle found in the nucleus
a positively charged particle found in the nucleus
a neutral particle that orbits the nucleus
This tells you how many protons are in each atom of a specific element and how many electrons there are in each unreacted atom from that element.
atomic number
atomic mass
chemical formula
chemical symbol
On the Periodic Table of Elements, this is the number below the chemical symbol and tells you how much mass is in a certain number of atoms for that element (you'll need to use this a LOT in high school chemistry).
atomic mass
atomic number
chemical symbol
mass
Select two words that describe this diagram
molecule
element
atom
compound
Select two words that describe this diagram
molecule
element
atom
compound
Select two words that describe this diagram
molecule
element
atom
compound
This is an example of what?
element
molecule
compound and molecule
