What is a physical change?
No new substance formed
Does atomic radius decrease or increase across a period?
Decrease
What type of bond shares electrons?
Covalent
What is the molarity of 2 moles in 1 L?
2M
What is pH + pOH?
14
Are fireworks a chemical or physical change?
Chemical
Is hydrogen a metal, metalloid, or nonmetal?
What is the arrhenius acid definition?
Produces H+ in water
(12.11+0.3) × (3.42/1.005)
*pay attention to sig fig calculation rules
42.2
A gas occupies 2.50 L at 1.20 atm and 300 K.
How many moles of gas are present?
0.122 mol
Define precision vs accuracy.
Precision = consistency; accuracy = closeness to true value
Which is more electronegative: Cl or Br?
Cl
What is the Brønsted-Lowry base definition?
Proton acceptor
Empirical formula of 40% C, 6.7% H, 53.3% O
CH2O
For the reaction: 2SO2(g) + O2(g) ⇌ 2SO3(g) ΔH<0
What happens to equilibrium if temperature is increased? What if pressure is increased?
Increase temperature = shifts left (endothermic direction favored). Increase pressure = shifts right (fewer moles of gas: 3 → 2)
Number of protons that defines the element
Which is bigger: Cl- or Cl?
Cl-
Does a precipitate form? BaCl2 + Na2SO4
Yes, BaSO4
Calculate the bond order of the carbonate ion (CO32-)
1.33
For a reaction with K=10 and Q=0.1 what happens?
Shifts right
Which trend increases across a period: atomic radius or ionization energy? (Bonus 100 points: give the definitions of atomic radius and ionization energy)
Ionization energy
Bonus:
Atomic Radius - size of an atom, from center of nucleus to outer electron shell
Ionization Energy - energy required to remove an electron
Write the electron configuration of Fe3+.
[Ar]3d5
Is this reaction redox, acid-base, or precipitation?
HCl + NaOH → NaCl + H2O
Acid-base
Chlorine has two naturally occurring isotopes:
The average atomic mass of chlorine is 35.45 amu.
What is the percent abundance of each isotope?
76% 35Cl and 24% 37Cl
A reaction has the rate law: rate=k[A]2[B]. What happens to the rate if [A] is doubled and [B] is tripled?
Rate increases by factor of 12