Matter & Mixtures
Which is an example of a solution: trail mix, carbon dioxide, salt water, pure water, or aluminum?
Salt water
What particle(s) are found in the nucleus of an atom?
Protons and neutrons
Which element has the largest atomic radius: Cu, He, K, N, or Br?
Potassium (K)
How many valence electrons does sulfur have?
6
Ionic bonds are best described as _____.
Attraction between oppositely charged ions
A chocolate chip cookie is an example of a(n) ____ mixture.
Heterogeneous mixture
How many total electrons are in the nitride ion (N³⁻)?
8 electrons (5 + 3)
Based on periodic table position, rubidium is most likely to _____.
Lose one electron and form a 1+ ion
Which of these bonds is covalent: O–N, Na–F, Ca–Br, Na–Cl, Mg–O?
Oxygen and nitrogen (both nonmetals → covalent)
Select the correct balanced equation for Mg reacting with O₂ (synthesis).
2 Mg + O₂ → 2 MgO
Which of these is not an example of matter: smoke, water, water vapor, air, or heat?
Heat
How many protons does the K⁺ ion have?
19 protons
Which is in the same period as phosphorus (P): N, O, Mg, C, or As?
Magnesium (Mg) (P is in Period 3)
What type of bond connects the nitrogen atoms in N₂?
Triple covalent bond
Select the correct balanced equation for Al reacting with HCl (single replacement).
2 Al + 6 HCl → 2 AlCl₃ + 3 H₂
CO₂ is a ____ (choose best): element, compound, pure substance, both b and c, both a and b.
Both compound and pure substance (both b and c)
An element has atomic number 50 and mass number 120. How many protons, neutrons, and electrons does it contain (neutral atom)?
50 protons, 70 neutrons, 50 electrons
Why do sodium and potassium have similar chemical properties?
They have the same number of valence electrons (1)
Which of the following is an ionic compound: CS₂, Kr, N₂O₄, PCl₃, or BaI₂?
BaI₂
For this reaction: FeCl₃ + Al(OH)₃ → ____ + ____ (name the products).
Iron(III) hydroxide + aluminum(III) chloride (Fe(OH)₃ + AlCl₃)
Explain the difference between a homogeneous mixture and a heterogeneous mixture using one example of each.
Homogeneous = uniform throughout (ex: salt water); Heterogeneous = not uniform (ex: trail mix / cookie).
Fill the missing logic: “All atoms are ____ with the number of ____ equaling the number of ____.”
Neutral; protons; electrons
What happens to atomic radius from left to right across a period, and why?
Radius decreases because nuclear charge increases while shielding stays about the same, pulling electrons closer.
The Lewis dot structure of SiO₂ shows ____.
Double bonds between silicon and oxygen (O=Si=O)
Balance and name the reaction type: ___ C₆H₁₄ + ___ O₂ → ___ H₂O + ___ CO₂
2 C₆H₁₄ + 19 O₂ → 14 H₂O + 12 CO₂; combustion