Atomic Structure and Elements
What subatomic particles make up an atom?
protons, neutrons, and electrons
What does the law of conservation of mass state?
Mass cannot be created or destroyed during a chemical reaction.
Which of the following is a homogenous mixture?
A. copper
B. salt
C. saltwater solution
D. muddy water
C. saltwater solution
What are the four states of matter?
Solids, liquids, gas, and plasma
Which show three changes of a physical change?
A. boiling water
B. juice freezing
C. iron rusting
D. bread burning
E. paper cutting
F. baking a cake
A. boiling water
B. juice freezing
E. paper cutting
An atom contains 22 protons, 43 neutrons and 22 electrons. What atom is being described?
Titanium
What is true about the mass of the contents in a closed container before and after a reaction occurs?
They are equal
How can you best describe a heterogenous mixture?
It is non-uniform and has no pattern. Can be separated physically
What happens to the movement of particles when thermal energy is added to a substance?
The particles move faster and it becomes warmer.
Which of the following is a chemical property?
A. reactivity with a base
B. density
C. ability to dissolve in water
D. melting point
A. reactivity with a base
What differentiates elements on the periodic table?
Their atomic number
In a reaction, reactant A is 37.23 grams and reactant B is 17.62 grams. According to the law of conservation, how many grams of product is formed?
54.85 grams
How can I differentiate between an element and a compound?
Elements contain one type of atom while compounds contain two or more different elements.
What happens to the movement of particles when thermal energy is removed from a substance?
The particles slow down and it becomes colder.
How can I determine that a chemical change has occurred?
A new substance is formed
What particles make up the atomic mass of an element?
protons and neutrons
A student observes one molecule of methane (1 carbon atom and 4 hydrogen atoms) react with tow molecules of oxygen (4 oxygen atoms). The product is one molecule of carbon dioxide (1 carbon atom and 2 oxygen atoms) and two molecules of water vapor (4 hydrogen atoms and 2 oxygen atoms). Is the mass conserved? Why or why not?
Yes because there are the same number of atoms on both sides.
What can be separated using chemical means only?
Compounds
When being transferred from one container to another, liquids will do what?
A. maintain their shape and volume
B. change both shape and mass
C. maintain their volume and change their shape
D. change their mass and maintain their shape
C.Maintain their volume and change their shape
Explain why the melting of ice is considered a physical change.
It involves a change in state but does not change its identity.
What is true about the nucleus of an atom?
The nucleus has a positive charge.
The nucleus is in the center of an atom.
The nucleus holds all the mass for the atom.
In a chemical reaction, what conclusions can be drawn if mass is lost in an experiment?
Mass can be lost due to gas, heat, leakage.
It is an open container.
Which of the following are compounds?
A. carbon dioxide (CO2)
B. sweet tea
C. copper (Cu)
D. salt (NaCl)
E. Air
F. Lead (Pb)
A. carbon dioxide (CO2)
D. salt (NaCl)
Arrange the substances from the MOST to the LEAST ordered particle movement.
Water, wood, neon gas
Wood, water, neon gas
What happens to the properties of a substance after a chemical reaction?
The physical and chemical properties change or are different however the amount of matter stays the same.