The average body temperature for humans is 98.6 degrees Fahrenheit. What is this temperature in degrees Celsius?
37 C
100
What is the concentration of chloride ion in a 2.5 M solution of lithium chloride?
2.5 M
100
what is the atomic number for oxygen?
8
100
how many moles of ions do you have if you have 1.0 mol sodium chloride?
2.0 moles
100
this element is the lightest noble gas
He
200
How many significant figures does the sum of 44.36 and 5.7 have?
Three sig. figs. (50.1)
200
What is the concentration of sodium ion in a 0.25 M sodium sulfate solution?
0.50 M
200
in the A-Z-X notation for atoms, A is the mass number, Z is the atomic number, and X is the chemical symbol. Which of these does NOT appear on the periodic table?
A, the mass number
200
what are the products of hydrocarbon combustion?
H2O and CO2
200
what is the oxidation state of osmium in OsO4?
+8
300
This term describes multiple measurements that are close to one another but not necessarily close to the true value.
Precise
300
A 100 mL sample of 0.05 M solution of sodium hydroxide is titrated with 0.10 M hydrochloric acid. What volume of hydrochloric acid is needed to reach the neutralization point?
50 mL
300
This neutral atom has 101 electrons and 157 neutrons. What is its chemical symbol?
Md, Mendelevium
300
What is the percent iron in a pure sample of iron (III) oxide?
Fe2O3, 70% iron
300
what is the oxidation state of chromium in potassium dichromate
K2Cr2O7 (ox state = +6)
400
A graduated cylinder has 11.2 mL water in it. A 5.00 g piece of ore is added and the water level rises to 13.7 mL. What is the density of the ore?
2.0 g/mL
400
Indicators are often a good way to look for the endpoint of a reaction. For the standardization of sodium hydroxide solution using oxalic acid, what indicator is used?
Phenolphthalein
400
What is the percent oxygen present in sulfuric acid?
H2SO4, 65.25% oxygen
400
Hydrogen gas reacts with nitrogen gas to form ammonia. If you start with 28.01 g of nitrogen gas, how many moles of ammonia can you make (theoretically)?
2.00 mole N2 because 3 H2 + N2 --> 2 NH3
400
What is the oxidation state of solid silver?
Zero
500
Silver has two isotopes that can be measured by mass spectrometry. One isotope has 60 neutrons and an abundance of 51.839%. The other isotope has 62 neutrons. What is the mass number for the second isotope?
109 (62 neutrons + 47 protons)
500
How many mL of a 1.00 M sulfuric acid solution are required to completely neutralize 4.00 g sodium hydroxide?
50 mL
500
Elemental analysis of a sample reveals that it contains 74.9% carbon and 25.1% hydrogen. The molar mass of the sample is 16.04 g/mol. What is the molecular formula?
CH4
500
Potassium chlorate decomposes into oxygen gas and potassium chloride. If you start with two moles of potassium chlorate, how many moles of oxygen gas do you produce (theoretically)?
3 moles O2 because 2 KClO3 --> 2 KCl + 3 O2
500
Aluminum solid will react with a solution of silver nitrate. What species in the reaction is the oxidizing agent?