Exam 2; chem for non majors
An air bubble has a volume of 0.25 L at 20 degreees C. What is the focal volume, in letters, of the gas when the temperature changes to 0 degrees C?
.23L
At STP, temperature and pressure have the values of ____.
0 degree Celsius and 1 atm
Balance the following equation: _N2H4 + H2O2 -> _N2+ _H2O
1,2,1,,4
How many of NH3 are in 32.0 g of NH?
1.88 mol
A tank contains helium gas at 1.50 atm. What is the pressure of a gaskin mmHg?
1140 mmHg
How many grams of CO2 are there in 4.50 moles of CO2?
198g
A sample of helium gas has a volume of 6.50 L at a pressure of 854 mmHg and a temperature of 25 degree Celsius. What is the final pressure of the gas, when the volume and temperature of the gas sample changed to 2.25 L and 12 degree Celsius?
2.4 x 10^3 mmHg
What is the ionic charge of an ion with 13 protons and 10 electrons?
3+
At STP, what is the volume of 2.00 moles of CO2 gas?
44.8L
One mole particle of any substances contains how many particles?
6.02x10^-23 particles
What is the molar mass of calcium hydroxide, Ca(OH)2?
74.10g/mole
The unit of 1 atmosphere used to describe the pressure of a gas is equal to ___.
760 mmHh
In the reaction below, how many moles of Al2O3 are produced when 12.6 moles of O2 reacts completely? 4Al+302->2Al2O3
8.4 mol
Which one of the following compounds contains an ion with a 3+ charge?
AlCl3
What is the formula of a compound that contains Ca^2+ and NO3- ions?
CA(NO3)2
The following reacts is an example of a _______ reaction. 2Na(s)+Cl2(g)-> 2NaCl(s)
Combination
The correct name for the compound CuS is ___.
Copper (II) sulfide
Which of the following best represent the bond between carbon and hydrogen in a CH4 molecule? H I H—C—H I H
Covalent bonds
The correct name of the compound N2O3 is _____.
Dinitrogen trioxide
A reaction that absorbs energy as it occurs is classified as a(n) _____.
Endothermic reaction
How many electrons will sulfure gain or lose when it forms an ion?
Gain 2
The shape of the methane molecule (CH4) is _____. H I H—C—H I H
Tetrahedral
In ionic compounds, ____ lose their valence electrons to form positively charged ____.
metals, cations
Which of the following for magnesium phosphide?
KCl
What is the correct name for LiNO3?
Lithium nitrate
In an oxidation-reduction reaction, the substance oxidation always ___.
Loses electrons
According to the kinetic theory of gases, particles of a gas ___.
Loses their valence electrons
What is the correct formula for magnesium phosphide?
Mg3P2
Which one of the following metals form two or more ions with different ionic charges?
Mn
In any balanced chemical equation, the number of each type of atom on both sides of the equations is
The same
(True or false ) the volume increases have the values of _____.
True