Scientific Basics
Name the diatomic elements
H2, N2, O2, F2, Cl2, Br2, I2,At2
Formula for calcium phosphate
Ca3(PO4)2
Write the mole ratio of hydrogen to oxygen
H2 + O2 --> H2O
2H2 + O2 --> 2H2O
2 mol H2 : 1 mol O2
What measurement describes the force applied over an area?
Pressure
Define solute, solvent and solution. Give examples of each.
Salt water - solution - mixture with uniform composition where the solute is dissolved in the solvent
salt - solute - substance being dissolved
water - solvent - substance doing the dissolving
Number of protons, neutrons and electrons in Mg+2
12 protons
12 neutrons
10 electrons
Chemical name for H2O
dihydrogen monoxide
Hydrogen gas reacts with nitrogen gas to form ammonia:
N2+3H2→2NH3
How many moles of ammonia are produced when 1.50 mol of nitrogen gas reacts with excess hydrogen gas?
3 mol NH3
What condition must exist for a liquid to boil?
atmospheric pressure must be equal to equilibrium vapor pressure
1.3 L of an aqueous solution containing 12.05 g of sodium chloride dissolved in pure water is prepared. Calculate the molarity of the solution.
0.16M
How many sig figs are in the number
0.00005006012590
10
Aqueous solutions of sodium chloride and barium sulfate are mixed, resulting in the formation of a two products. The most chemical formula of one of the products is
Na2SO4 or BaCl2
Sodium reacts with chlorine gas to form sodium chloride: Na+Cl2→ NaCl
How many grams of sodium chloride are produced when 11.5 g of sodium reacts with excess chlorine?
29.22 grams NaCl
Explain the triple point on a phase diagram
the point where all 3 states of matter coexist at equilibrium
Which element is the most electronegative?
Fluorine
Explain the difference between a chemical and physical change and give an example of each
chemical change results in a NEW substance - bunsen burner
physical does not - melting
Identify the type of reaction below, predict the products, and balance
Al + Mg(OH)2 -->
Single Displ.
2Al + 3Mg(OH)2 --> 3Mg + 2Al(OH)3
Magnesium reacts with hydrochloric acid:
If 6.00 g of Mg reacts with 7.30 g of HCl, what is the limiting reactant, and how many grams of hydrogen gas are produced?
HCl is limiting
0.202 g H2
A 15.0 L sample of gas at 25oC is heated to 50oC. What is the new volume?
16.3L
Define equilibrium.
Forward and reverse reactions occur at the same rate.
Opposing processes occur at the same rate
How many molecules are in 212g of C6H12O6?
7.08E23
Balance the equation:
C7H6O2 + O2 --> CO2 + H2O
2C7H6O2 + 15O2 --> 14CO2 + 6H2O
Calcium carbonate decomposes:
CaCO3→CaO+CO2
If 50.0 g of CaCO₃ is heated and only 18.0 g of CaO is collected, what is the percent yield of CaO?
64.3%
List and describe each phase change
Condensation
Vaporization
Freezing
Melting
Sublimation
Deposition
What is the final concentration when 500 mL of water is added to 200 mL of a 3 M NaCl solution
0.86 M