Molecular Geometry & Theory
What is the molecular geometry of methane (CH₄)?
Tetrahedral
Properties of ionic compounds involve the formation of a ____ and a ____
cation (+) and an anion (-)
A white solid melts at a very high temperature. When dissolved in water, the solution conducts electricity. What is this solid most likely made of?
Ions
A reaction happens faster when the temperature is increased. What is the main reason for this?
The particles collide more often and with more energy.
Find atoms in 2 moles of Helium (He).
1.204×1024 atoms
Which theory helps us predict the shape of a molecule?
VSEPR theory
What is the charge on the ion typically formed by an element in Group 2 of the periodic table?
2+ (e.g., Mg2+, Ca2+)
Which element is a non-metal?
Hydrogen, Carbon, Nitrogen, Oxygen, Phosphorus, Sulfur, Selenium, Fluorine, Chlorine, Bromine, Iodine, Astatine, Helium, Neon, Argon, Krypton, Xenon, Radon, and Oganesson
When something burns and feels hot, the reaction is:
Exothermic
Find moles in 90g of water (H2O, M=18g/mol)
5 mol
In the chemical formula H2SO4, how many oxygen atoms are present in one molecule?
4
What is the formula of Rubidium Oxide?
Rb₂O
How many elements are there in the periodic table?
118
In an acid-base titration, what is a common indicator, and what color does it change to?
Phenolphthalein. Pink.
Find the mass of 2 moles of NaCl (M=58.5g/mol)
117 grams
How many significant figures are in this number? 0.600
3
What is the formula of Magnesium Phosphate?
Mg₃(PO₄)₂
What type of bond is present in metals?
Metallic bond
What is titration?
A titration lab is a systematic method for determining the concentration of an unknown substance by slowly adding a known solution (titrant) to the unknown (analyte) until a reaction is complete, signaled by an indicator changing color (such as phenolphthalein from colorless to pink).
Find molecules in 9g of water.
Step 1: Moles = 9 ÷ 18 = 0.5 mol
Step 2: Molecules = 0.5 × 6.022×10²³ = 3.011×10²³ molecules
Which rule does not apply to scientific notation?
Leading zeros are significant
Which type of bond involves the transfer of electrons from one atom to another?
Ionic bond
A chemical bond is an attraction between two or more ___ that form a chemical.
Atoms
How many electrons does Metals of 1-3rd Groups have on the outer shell?
a) 1-2 b) 1-3 c) 4-7 d) 6-8
b) 1-3
How many moles are in 3 moles of carbon (C)?
3 moles