Chemistry Quizes- Semester 2
If the volume of a gas at 323 K is changed from 780 mL to 620 mL at constant pressure, what will the new temperature of the gas be in Celsius?
-16 degrees Celsius
convert 40 degrees K to Celsius
-232 degrees Celsius
You travel to big bear with your family. The temperature outside has been 20 Celcius and it has been raining for the past month. Do you expect there to be a great deal of natural snow on the ground? explain reasoning
-No snow -no there wouldn't be snow because it would be 68 degrees fareinheit and for it to snow it needs to be 32 degrees farenheit. Also because the freezing point for celsius is zero and the temperature is 20 Celsius so it wouldn't be cold enough to snow
How many moles of potassium iodide, KI are there in 50 grams -0.3 mol -2.20mol -3.32 mol -166 mol
0.3 mol
Calculate the molarity of hydrochloric acid HCl is 25 mL of the solution is neutralized by 15.5 mL of 0.800 M NaOH. 0.645 M 0.0428 M 0.496 M 1.29 M
0.496 M
The specific heat capacity of hydrogen is 3.34 cal/g x C. Whats the temp change of 200 g of hydrogen if 500 cal of heat are added? 16.7 degrees Celsius 8.4 degrees Celsius 1.5 degrees Celsius 0.75 degrees Celsius
0.75 degrees Celsius
Balance chemical equation ___ Fe2O3 + _____ H2 (g) ---> _____ Fe (s) + _____ H20(l)
1,3,2,3
How many atoms are there in 1 mole of CO2 -1.8 x 10^23 atoms -6.02 x 10^23 atoms -1.8 x 10^24 atoms -6.02 x 10^24 atoms
1.8 x 10^24 atoms
At a pressure of 1 atm, the volume of a balloon is 2.7 L. Assuming that the temperature remains constant, what will the volume of the balloon be if the pressure is increased?
1.9 L
A piston contains a sample of gas at pressure x. If the volume of the position triples with constant temperature and amount of gas, the pressure becomes: -3x -1/3 x -9x -cannot be determined
1/3 x
If 10mL of 0.085 M HCl (aq) is diluted with water, what is the final volume in order to have pH= 5.07? 100 mL 1000 mL 10 L 100 L
100 L
Which solution will neutralize 100 mL of a strong acid that has a pH of 4? 100 ml of 0.1 M NaOH 100 mL of 0.01 M NaOH 100 mL of 0.001 M NaOH 100 mL of 0.0001 M NaOH
100 mL of 0.0001 M NaOH
Which of these materials has the most moles of metal atoms? -100g iron, Fe -100 g iron (II) oxide, FeO -100 g potassium chloride, KCl -100g potassium, K
100g potassium, K
What's the pH of 0.0048 M NaOH?
11.68
The adult LD50 for aspirin is 400 mg/kg. How many 250 mg aspirin tablets would a 175 lb person need to consume to get a lethal dose? (1kg=2.2lb)
127 tablets
What's the molar mass of ammonium phosphate (NH4)3PO4 -149 g/mol -113 g/mol -242 g/mol -121 g/mol
149 g/mol
What's the value of [H+] of a solution is the pH is 5? 1x 10^-5 M 1x 10^5 M 5x 10^-7 M 5x 10^5M
1x 10^-5 M
How many moles of phosphoric acid H3PO4 would be produced if 142 g of P4O10 were reacted? (MM P4O10=284.89 g/mol) P4O10 (s) + 6 H2O(l) ---> 4H3PO4 (aq) 0.25 mol 0.5 mol 2 mol 4mol
2 mol
At 300 K, the pressure inside a rigid can is 2.2 atm. If the temperature increases to 315 K whats the pressure inside the can?
2.3 atm
Nitric acid is formed by the reaction of nitrogen dioxide with water. How many moles of water are need to react with 8.4 mol of nitrogen dioxide? 3NO2 (g) + H20(l)---> NO (g) + 2HNO3 (aq) 2.8 3 8.4 25
2.8
How many grams of aluminum are contained in 100 g of aluminum chloride, AlCl3? -18.6 g -20.2 g -25 g -21.5 g
20.2 g
What's the mass of 222 mL of ice if the density of ice is 0.92 g/mL? -414 g -241 g -222 g -204 g
204 g
Iron (III) oxide is formed when iron combines with oxygen. What mass of Fe2O3 will be produced when 16.7g Fe reacts with 16.7g oxygen? (MM Fe2O3=159.7) 4Fe (s) + 3O2(g)---> 2Fe2O3(s) 12.8 g 23.9g 47.8g 95.6g
23.9g
heat of fusion of water is 79.9 cal/g and the heat of vaporization of water is 539 cal/g. What amount of heat is released when 50 g of water condenses at 100 degrees Celsius 5000 cal 26950 cal 7990 cal 39,950,000 cal
26950 cal
How many grams of sodium hydroxide would you need to produce 75 g of lead (II) hydroxide (MM Pb(OH)2= 214.21 g/mol) 2NaOH(aq) + Pb(NO3)2 (aq)---> 2NaNO3 (aq) + Pb(OH)2 (s) 13.1 g 28 g 52.4 g 75 9
28 g
Write balanced chemical equation for the neutralization of acetic acid by calcium hydroxide
2HC2H3O2 + Ca(OH)2----> Ca (C2H3O2)2 + 2H2O
How many grams of sugar (LD50=30 g/kg) would be lethal to a 220 pound man? (2.2 lb=1 kg)
3000g
What's the final temp of the water when 450 mL of 30 degrees celsius water is mixed with 250 ml of 60 degree Celsius water 36 degrees celsius 41 degrees celsius 55 degrees celsius 90 degrees celsius
41 degrees celsius
According to the balance equation, how much moles of copper are required to produce 10 mol of silver? Cu(s) + 2AgNO3(aq) ---> 2Ag(s) + Cu(NO3)2 (aq) 20 10 15 5
5
At 20 Celcius a gas has a volume of 4.75 L. What will be the volume of the gas at 90 Celsius?
5.88 L
A student titrates a 100 mL sample of 0.50 M HCl (aq) with 0.10 M MaOH (aq). What volume of titrant is requited to reach the equivalence point?
500 mL= Vb
A tank of medical, oxygen has a volume of 35.4 L and contains O2 at 151 atm and 25 Celsius. What volume of O2 does this correspond to at normal body conditions, 1 atm and 37 Celsius?
5560 L
Lead (II) nitrate can be decomposed by hearing. What is the percent yield if 9.9 g Pb(No3)2 (g)---> 2PbO(s) + 4NO2 (g) 44% 56% 67% 82%
82% actual -------- theoretical
A balloon is filled at sea level with 75L of air at 28 celsius. the balloon is taken to the top of a mountain where the pressure is 0.8 atm and the temperature is 18 celsius. What's the new volume of the balloon?
90.6 L
Which of the following would be the best choice for treating a lake damaged by acid rain? -NaCl -HC2H3O2 -CH3OH -Ca(OH)2
Ca(OH)2
Write a Skelton equation including state symbols for the following description: Copper (II) carbonate is heated to 600 C to form copper (II) oxide and carbon dioxide
CuCO3 (s) ----> CuO(s) +CO2 (g)
If a sample of air freshener is sprayed at the back of the chemistry room, it will take a little time for those sitting in the front of the room to smell it. According to kinetic molecular theory this is because: -Gas particles travel in straight-line paths, but the distance to the front of the room is far and gas particles move slowly -Gas particles move at high speeds but frequently collide with other gas particles -the gas particles in the air freshener have less kinetic energy than the gas particles in the room -the air freshener gas particles stay at the back of the room
Gas particles move at high speeds but frequently collide with other gas particles
Given two solutions, 0.10M HF and 0.10M HCl, will they conduct electricity equally well? If not, which will conduct better? Explain your reasoning?
HCL will conduct electricity better than HF because its a strong acid -both will conduct electricity because acids are electrolytes in aqueous solutions
Which statement is true about the end product after a substance has undergone sublimation? -It is at a lower density -It has a lower volume -It is a solid -It is a liquid
It is at a lower density
If you have 1 mol of each of the following compounds, which will have the greatest mass? -H3PO4 -KCl -FeCl3 -NI3
NI3
Which chemical equation represents a physical change -2Li (s) + 2H20 (l)---> 2LiOH (s) + H2(g) -2CH3OH(l) + 302 (g) --->2CO2(s) + 4H20(g) -2H2(g) + O2 (g) ---> 2H2O (g) -NaCl (s) ---> NaCl (aq)
NaCl (s) ---> NaCl (aq)
Identify the strong base NH3 NaOH NaC2H3O2 C2H5OH
NaOH
In the reaction shown by the equation below, what is the limiting reactant if you have 100 g of NaOH and 100 g of Al? 6NaOH (aq) + 2Al (s)---> 2Na3AlO3 (s)+ 3H2 (g) Na3AlO3 Al NaOH H2
NaOH
Which gas law would be most appropriate for solving a gas law problem involving a rigid container V=kT P=kT P=k(1/V) D=m/V
P=kT
Which compound is one of the products of the double exchange reaction below? NaCl+ Pb(NO3)2 ---> _______ + _________ -Na2Pb -CINO3 -Na(NO3)2 -PbCl2
PbCl2
suppose you mix potassium chloride and lead (II) nitrate solutions. What's the precipitate that forms? -PbCl -PbCl2 -K(NO3)2 -KNO3
PbCl2
A student places 30 mL nitric acid in a flask along with 4 drops of phenolphthalein. she adds titrant (0.20 NaOH) until the solution becomes a deep bright pink. a) calculate initial concentration of acid if 42 mL of titrant was dded b) the true value of nitric acid concentration is 0.25 M HNO3. Calculate percent error
a) 0.28 M= M1 b) 12% is the percent error
Consider the following solutions : 1M NH3 and 1M KOH. a) which one conducts electricity better? b)explain
a) 1M KOH b because it is a stronger base than NH3 is, so it will be a better conductor of electricity
write dissociation equations for the following acids a) HNO3 b) HF
a) HNO3------> H+ + NO3- b) HF-----> H+ + F- <-----
Which action raises the temp of a cup of water the most adding 200 cal to 100 g of water at 30 degrees celsius adding 100 cal to 50 g of water at 30 degrees celsius adding 700 cal to 400g of water at 30 degrees celsius adding 500cal to 200g of water at 30 degrees celsius
adding 500cal to 200g of water at 30 degrees celsius
When energy changes from one form to another -all the energy can be accounted for -some of the energy is lost entirely -a physical change occurs -all the energy is transformed into work
all the energy can be accounted for
Given equal masses which of these substances occupies the greatest volume? -gold (19.32 g/ml) -aluminum (2.70 g/ml) -barium (10.07 g/ml) -tin (7.31 g/mol)
aluminum (2.70 g/ml)
Jake measures the weight of one bottle cap as 5.03 grams, so he calculates that the weight of 100 bottle caps will be 503 grams. The actual weight of 100 bottle caps is 495 grams. What's Jake's percent error?
calculated-actual ----------------- x 100 actual -1.6%
What type of chemical reaction is represented by this equation? H2CO3(aq)---> CO2 (g) + H2O (l) -decomposition -combination -double exchange -single exchange
decomposition
Which statement below is true based on the second law of thermodynamics -energy transfers from colder to hotter objects during an endothermic process -energy transfers always involve a temperature change -energy always transfers from hotter to colder objects -energy is never transferred during a physical process
energy always transfers from hotter to colder objects
Which of these conditions is always true for an exothermic process? -energy is transferred to the environment -the temperature decreases during the process -molecules move more slowly at the end of the process -a chemical reaction occurs
energy is transferred to the environment
Which of the following observations cannot be predicted from a chemical equation? -solid precipitate forming in a liquid -flash of bright light -bubbles forming in a liquid -liquid disappearing
flash of bright light
Which information can you determine about a chemical reaction from a complete chemical equation? -color of the products -how fast reaction occurs -how much energy is released as head -formation of a solid precipitate
formation of a solid precipitate
Gas pressure is caused by: -gravity -gas molecules colliding with other gas molecules -gas molecules colliding with surfaces -gas molecules reacting with other gas molecules
gas molecules colliding with other gas molecules
For a sample of gas in a balloon at constant pressure, if the volume of a gas decreases, then the temperature of the gas: -is decreasing -is increasing -remains constant -cannot be determined
is decreasing
What's an example of chemical change? -Water vapor condenses to form a cloud -air temperature increases energy is absorbed from the sun -air pressure drops on a stormy day -lightning strike forms ozone, O3, from oxygen gas
lightning strike forms ozone, O3, from oxygen gas
Which pair of solutions will produce a precipitate when they are mixed? -mercury (I) nitrate -Magnesium sulfate and zinc (II) nitrate -sodium phosphate and cesium chloride -lithium acetate and potassium phosphate
mercury (I) nitrate and sodium hydroxide
In a balanced chemical equation, which of the following is conserved? -subscripts -number of moles -phases -number and type of atoms
number and type of atoms
What's the pH of a solution of 4.5 x 10^-5 M HNO3? pH= 4.35 pH= 4.5 pH= 8.81 pH=11.19
pH= 4.35
What's the pH of the solution which results from diluting 5 mL of 0.062 M NaOH to a final volume of 200 mL pH=2.81 pH=6.20 pH=8.81 pH=11.19
pH=2.81
Ag(s) + CuI(aq) --> AgI(s)+ Cu (s) is an example of -physical change -single exchange -a combination reaction -decomposition reaction
single exchange
Which of the following is true about limiting and excess reactants? -both reactants are left over after a reaction is complete -a balanced chemical equation is not necessary to determine which reactant is limiting -the amount of product obtained is determined by the limiting reactant -the reactant that has the smallest given mass is the limiting reactant
the amount of product obtained is determined by the limiting reactant
A ballon occupies a greater volume at room temperature than at 0 degrees Celcius. This is because: -temperature is inversely proportional to volume -the density of particles is greater in the warmer balloon -the molecules in both balloons have the same average kinetic energy but the particles are at different speeds -the gas molecules in the room temperature balloon have a higher average kinetic energy than when gas molecules are at 0 Celsius
the gas molecules in the room temperature balloon have a higher average kinetic energy than when gas molecules are at 0 Celsius
You are holding 2 helium balloons at room temperature, one large, and one small. How do the pressures of helium compare? -the larger ballon has higher pressure because it has a larger volume than the smaller balloon -the smaller balloon has higher pressure because its volume is smaller than the larger volume -the pressure in each balloon is about the same as the atmosphere -the pressure cannot be determined
the pressure in each balloon is about the same as the atmosphere
25 mL of 0.40 M HCl (aq) is combined with 95 ml of 0.20 M NaOH (aq). Is the solution acidic, basic, or neutral?
the solution is more basic
What substance is the least toxic? -chlorine (LD50= 850 mg/kg) -aspirin (LD50= 200 mg/kg) -cola (LD50=140 mg/kg) -vitamin A (LD50=2000 mg/kg)
vitamin A (LD50=2000 mg/kg) -because you have to eat alot of this for it to be toxic
Which of these is likely to have the highest specific heat? aluminum, Al copper,Cu methanol, CH3OH water, H2O
water, H2O
According to Arrhenius, an acid is a substance -which can remove a hydrogen ion from another substance -which can remove a hydroxide ion from another solution -which adds hydrogen ion to solution -which is amphoteric
which adds hydrogen ion to solution
Does the chemical equation below demonstrate the law of conservation of mass? CH4(g)+ 2O2 (g) ---> CO2 (g) + 2H2O(l) -yes because there are the same number of molecules of reactants and products -yes because there are the same number of atoms of each element in reactants and products -no because one of the products is a liquid, not a gas -no because there are different compounds on the two sides of the arrow
yes because there are the same number of atoms of each element in reactants and products
