DAT DESTROYER Q's Flashcards
The specific heat of a metal is 0.90 J/g. If 50 g of the metal initially at 20 degrees celsius is heated with 10 kJ of heat, what is the final temperature of the metal?
Use Q = mcΔT formula!
10,000 = (50) (.90) (ΔT)
10,000 = 45 Δ T
ΔT = 222
222 + 20 + 273 = 515
Decay chart
A chemist needs to calculate the molarity of a salt solution. Which of the following is needed for calculation?
1) mass of salt added
2) molecular mass of the salt
3) solution volume
4) volume of water added
2, 3, and 4
The conjugate acid and conjugate base of HSO3- are:
H2SO3 and SO3–
for the acid - add an H and increase the charge by 1
for the base - decrease an H and in crease charge by 1
Which of the following ions has the largest radius?
a) S–
b) F-
c) Ne
d) K+
e) Ca++
A
if periodic trend does not solve this type of question, find the ion with the most negative charge
Molecular solids have (low/high) melting points, while ionic solids have (low/high) melting points
molecular solids = low MP
ionic = high MP
What is the relationship between Ksp and solubility?
Decrease Ksp = decreased solubility
increase Ksp = increased solubility
proportional relationship!
Why do solutes increase the boiling point of a solution?
The solute particales lower the solvents vapor pressure, causing a higher temperature to boil
In regards to quantum numbers, when l (azimuthal number) = 0, m (magnetic) must equal ____
0
How many unpaired electrons are in Molybdenum (Mo)?
6
T/F? Isotopes have virtually identical chemical and physical properties.
T/F? At -40 degrees celsius, we are also at -40 degrees farehnheit
TRUE
TRUE
What is the pH of a 1.0 x 10-4 M Ca (OH)2 solution?
use exponent given in molar = 4
Because it’s a base, substrat 4 from 14 = 10
Given the reaction
2NOBr (g) -> 2 NO (g) + Br2 (g)
What will provide a shift to the right?
a) increase in pressure
b) decrease in ptemperature
c) remove some NOBr
d) increase the container volume
D
An increase in pressure will drive the reaction towards (higher/lower) volume
Decreasing temperature will shift the reaction to the ______
An increase in volume will drive the reaction towards the side with (less/more) volume
lower, left, more
A solution of LiCl has a density of 1.13 g/cm. If the solution is 20% by weight LiCl, what is the molarity?
20% = 20 g/100 g of solution
20g / 100 g soltiion x 1.13 / 1 mL x 1000 mL / L x 1 mol LiCl / 42 g
= 5
Increasing the temperature in a reaction will favor the ______ reaction, while decreasing temperature will favor the _____ reaction
a) exothermic, endothermic
b) endothermic, exothermic
c) exothermic, exothermic
B
Which salt would have its solubility most affected by pH change?
a) CuCl
b) AgBr
c) BaF2
d) AgI
C
its a weak acid
Given a set of atoms that are all stable, how can you determine which has the greatest ionization energy?
Find the SMALLEST atom
small = great ionization energy (if all atoms are stable)
Consider a vessel with argon gas. This vessel is now replaced with helium gas. If both vessels contain 10 moles of gas, which is true?
a) pressure of the container will change
b) temperature of the container will change
c) the density of the container will change
d) the bumber of molecules in the container will change
C
pV = nRT
If the number of moles do not change ( as given in the question), then temperature, pressure, and volume will not change either!
Which of the following is amphoteric?
a) NO2-
b) HSO3-
c) CN-
d) NH4+
e) PO43-
B
an amphoteric species can act as an acid or a base; it must have an H+ ion to donate or receive!
The Ksp of Ag2PO4 is approximately 2x10-10
Which of the following would increase the Ksp?
a) add a solition of Na3PO4
b) raise the pH
c) lower the pH
d) add AgCl
e) none of the above
E
NOTHING CHANGES KSP EXCEPT THE TEMPERATURE
When one atom donates both electrons, what type of bond is formed?
a) ionic
b) network covalent
c) coordinate covalent
d) hydrogen bond
e) dispersion attraction
C
network covalent bond - atoms are bonded by covalent bonds in a continuous network extending throughout the material
ionic bond - metal and nonmetal
Which of these cannot be a ligand?
a) H2O
b) Cl-
c) N2H4
d) NH3
e) C2H2
E
a ligand must have lone pairs!
The more reactants a reaction has, the (more/least) like a reaction will occur
LEAST
