Unit 1
Which of the following units is an SI base unit?
kilogram
Oxygen-15 is an isotope that has an atomic number of 8. What can you conclude with this information?
Oxygen-15 has 8 protons and 7 neutrons.
Which option describes nonmetals?
They conduct electricity poorly.
Name the types of radiation from largest particles to the smallest
Alpha, Beta, Gamma
Which term correctly describes two liquids that form a heterogeneous mixture when combined?
immiscible
An object has a mass of 50.0 g and a volume of 10.5 cm3. Whats the density of the object?
4.76 g/cm3
What happens when an electron emits a photon?
An electron emits a photon and falls from a higher energy level to a lower energy level.
When an alkali metal is involved in a chemical reaction with a nonmetal, what charge will its atoms most likely form?
1+
What percentage of a radioactive isotope remains after 4 half-lives?
6.25%
What is the difference between a strong acid and a weak acid?
A strong acid will produce a larger amount of ions than a weak acid.
Which physical properties would change depending on how much of a substance you were measuring?
Mass and Volume
What principle states the law of conservation of mass and the law of conservation of energy?
Energy and mass cannot be created or destroyed during physical changes or chemical reactions.
Given that bromine (Br) is a halogen, what can be inferred as true about bromine?
Bromine tends to form anions when in chemical reactions with metals
What happens to the half-life and mass of reactants broken down during a nuclear decay reaction?
The half-life of reactants in a nuclear decay reaction remains constant over time, but the mass of reactants that are consumed decreases.
Yasmin's teacher asks her to make a supersaturated saline solution. Her teacher tells her that the solubility of the salt is 360 g/L at room temperature (25 °C). How can Yasmin make a supersaturated saline solution?
She can add 380 g of salt to 1 L of hot water (75 °C) and stir until all the salt dissolves. Then, she can carefully cool the solution to room temperature (25 °C).