stoich test 1 and 2

the figure above represents three sealed 1.0 vessels, each containing a different inert gas at 298 K. The pressure of Ar in the first vessels is 2.0 atm. The ratio of the number of Ar, Ne, and He atoms in the vessels is 2: 1: 6 respectively. After all the gases are combined in a previously evacuated 2.0 L vessel, what is the total pressure of the gases at 298K

e none of these

Absorption is the process of releasing energy. It usually involves moving an electron from a low energy state to a higher energy state.

false

The top spectrum with the black background shows light being absorbed by a sample of hydrogen

false

which container is most likely to break the laws of ideality

gas a

The Graph above shows the speed distribution of molecules in a sample of a gas at a certain temperature. Which of the following graphs shows a speed distribution of the same molecule at a lower temperature

graph d (closest together)

Under the conditions given consider containers 1, 2, and 4 only. The average speed of the gas particles is

greatest in container 1 (He)

The best explanation for the lower pressure in container 4 is that SO2

have stronger intermolecular attractions than the other three gases

The volume of a sample of air in a cylinder with a movable piston is 2.0 L at a pressure P1 as shown in the diagram above. The volume is increased to 5.0 L as the temperature is held constant. The pressure of the air in the cylinder is now P2. what effects do the volume and pressure changes have on the average kinetic energy of the molecules in the sample

the average kinetic energy stays the same

For an isoelectronic series of ions, the ion that is the smallest is always

the ion with the highest atomic number

2MnO4- (aq) +5 C2O42- (aq) + 16 H+ (aq) → 2Mn2+ (aq) +10 CO2(g) + 8 H2O (l) permanganate and oxalate ions react in and acidified solution according to the balanced equation above how many moles of CO2(g) are produced when 20. ml of acidified 0.20 M KMnO4 solution is added to 50. ml of 0.10 M Na2C2O4 solution

0.010

A 0.20 mol sample of MgCl2 and a 0.10 mol sample of KCl are dissolved in water and diluted to 500 ml what is the concentration of Cl- in the solution

1

for the reaction 2S +3 O2 → 2 SO3 how much SO3 can be produced from 7.08 g O2 and excess S

11.8

. . . C10H12O4S(s) + . . . O2(g) → . . . CO2(g) + . . . SO2(g) + . . . H2O(g) When the equation above is balanced and all coefficients are reduced to their lowest whole-number terms, the coefficient for O2(g) is

12

LiHCO(aq) +H2SO4(aq) → LiSO4(aq) + H2O(l) + CO2(g) when the equation above is balanced and the coefficients are reduced to the lowest whole number terms what is the coefficient of H2O(l)

2

C3H8(g) + 5 O2 (g) <-----> 3 CO2 (g) + 4 H2O (l) In the reaction represented above what is the total number of moles of reactants consumed when 1.00 mole of CO2(g) is produced

2.00

What volume of solvent should be added to 36.8 g of CH3OH to produce a 0.500 M solution of CH3OH

2.30

H2+ F2 → 2HF In the Reaction represented above what mass of HF is produced by the reaction of 3e1023 molecules of H2 with excess F2

20.

a 6.0 mol sample of C3H8 and a 20. mol sample of Cl2 are placed in a previously evacuated vessels, where they react according to the equation above. After one of the reactants has been totally consumed how many moles of HCL have been produced.

20. mol

According to these periodic tables how, many protons are in one molecule of carbon dioxide

22

Li3N(s) + 2 H2(g) → LiNH2 (s) + 2 Li H(s) Because pure H2 is a hazardous substance safer and more cost-effective techniques to store it as solid for shipping purposes have been developed one such method is the reaction represented above which occurs at 200 degrees Celcius when 70.35 g Li3N(s) reacts with excess H2(g) 8.00 g of LiH(s) is produced the percent yield is closest to

24.9

Under which of the following conditions of temperature and pressure will H2 gas be expected to behave most like an ideal gas

500 K and 0.10 atm

A red photon has a frequency of 4.58e14. What is the wavelength of this light m and nm? What is the amount of energy in one photon? What is the amount of energy in a mole of photons?

6.55e-7 meters, 655 nm, 3.03e-19 J, 183 kJ/mol

CO2(g) + 2LiOH(s) --> Li2CO3(s) + H2O(l) In a person's spacecraft, an astronaut exhales 88.0 g of CO2(g) per day. To prevent the buildup of CO2(g) in a spacecraft a device containing LiOH(s) is used to remove the CO2(g) as represented by the equation above. What mass of LiOH(s) is needed to react with all of the CO2(g) produced by an astronaut in one day

958

The first five ionization energies of unknown elements are listed in the table above. Which of the following statement correctly identifies the element and cites the evidence supporting the identification

Al, because of the large difference between the third and fourth ionization energies

According to the information in the table above a 1.00g sample of which of the following contains the greatest mass of oxygen

B

What is the empirical formula of an oxide of chromium that is 48 percent oxygen by mass

Cr 1 O3

Write an equation that represents the second ionization energy of cooper

Cu+ -> Cu2+ + e-

A sample of a solid labeled as NaCl may be impure. A student analyzes the sample and determines that it contains 75 percent chlorine by mass. Pure NaCl contains 61 percent chlorine by mass. Which of the following statements is consistent with the data

D

Which of the following particle diagram best represents the products when four molecules of H2O2(l) decompose into water and oxygen gas at room temperature

D

The experimental apparatus represented above is used to demonstrate the rates at which gases diffuse. When the cotton balls are placed in the ends of tube at the same time, the gases diffuse from each end and meet somewhere in between where they react to form a white solid which of the following combination will produce a solid closest to the center of the tube

HCl and CH3NH2

a 0.5 mol sample of He and a 0.5 mol sample of Ne are placed separately in two 10.0 L rigid containers at 25 C each container has a pinhole opening. which of the gases He or Ne will escape faster through the pinhole

He will escape faster because the He atoms are moving at a higher average speed than the Ne atoms

When Hafnium is heated in an atmosphere of chlorine gas. the product of the reaction is found to contain 62.2 percent Hf by mass and 37.4 percent Cl by mass. What is the empirical formula for this compound

Hf 1 Cl 3

Which of the following statements about the periodic trend of the atomic radius is/are true

I and III only

Based on the Information above and periodic trends, which of the following is the best hypothesis regarding the oxide(s) formed by Rb

Rn will form Rb2O , RB2O2, and RbO2

If a pure sample of an oxide of sulfur is 40% S and 60% O by mass, what is the empirical formula of this sample?

S 1 O 3

Based on Coulomb's law and the information in the table above which following anions is most likely to have the strongest interaction with nearby water molecules in an aqueous solution

S2-

Which of the following can be inferred from the diagram above that shows the dependence of potential energy on the internuclear distance between two atoms

The atoms form a bond with a bond length of 75 pm

Assuming that these gases (A,B, and C) are in containers of the same volume and that these three curves represents the same number of moles of three different molecules at the same temperature which one is exerting more pressure on its container

They are all exerting the same pressure

Based on the ionization energies of element X given in the table above which of the following is most likely the empirical formula of an oxide of the element X

X2O3

The ionization energies of an unknown element, X are listed in the table above. Which of the following is the most likely empirical formula of a compound formed from element X and phosphorus P

X3P2

Which of the following periodic trends is inversely proportional to the effective nuclear charge

atomic radius

If equal masses of the following compounds undergo complete combustion, which will yield the greatest mass of CO2

benzene C6H6

When an electron is added to a gaseous chlorine atom, 349 kJ/mol of energy are released. What is the ionization energy of a gaseous chloride ion?

+349 K

Au2 S3 + 3 H2 → 3 H2 S + 2 Au What mass of Au is produced when 0.0500 mol of Au2S3 is reduced completely with excess H2

19.7

Assuming that this radiation is traveling through a vacuum what is its frequency in hertz

2.1e16

An 8.00 sample of copper ore was dissolved in acid solution and then reacted with NO3- from a KNO3 salt solution 3Cu+ 8 NO3- +8H+ → 3 Cu2+ +2NO +4 H2O +6 NO3- it required 71.5 ml of a 0.155 M KNO3 solution to fully react the copper in the ore sample what was the percent copper in the ore

3.30

10 HI+ 2KMnO4+ 3H2SO4 → 5I2 +2MnSO4 + K2SO4 + 8 H2O according to the balanced equation above how many moles of HI would be necessary to produce 2.5 mol of I2 starting with 4.0 mol KMnO4 and 3.0 mol of H2SO4

5.0

The first ionization energy of an element is the energy required to remove an electron from a gaseous atom of the element. The values of the first ionization energies for the third-row elements are shown in the graph above. On the basis of the information given which of the following reactions is exothermic

Al + Mg+ -> Al+ + Mg

A mixture of H2(g) and O2(g) is placed in a container as represented above. The H2(g) and O2(g) react to form H2O(g). Which of the following best represents the container after the reaction has gone to completion.

B

A sample of a compound that contains only the elements C,H, and N is completely burned on O2 to produce 44.0 g of Co2, 45.0 g of H2O, and some NO2. a possible empirical formula of the compound is

B

K(s) + 1/2 Cl2(g --> KCl(s) ∆H° = −437 kJ/molrxn What remains in the reaction vessel after equal masses of K(s) and Cl2(g) have reacted until either one or both of the reactants have been completely consumed? (A) KCl only (B) KCl and K only (C) KCl and Cl2 only (D) KCl, K, and Cl2

C

Which of the following particulate diagrams best shows the formation of water vapor from hydrogen gas and oxygen gas in a rigid container at 125 degrees Celcius

C

A 23.0 g sample of a compound contains 12.0g of C, 3.0g of H, and 8.0 of O. Which of the following is the empirical formula of the compound

C 2 H6 O 1

The table below contains information about samples of four different gases at 273 K. The samples are in four identical rigid containers numbered 1 through 4. On the basis of the data provided above, the gas in container 3 could be

Ch4

On the basis of the information above which of the following arranges the binary compounds in order of increasing bond policy

Ch4< SiCl4< SF4

Based on Coulomb's law and the information in the table above which of the following is most likely to have the weakest interactions with adjacent water molecules in an aqueous solution

Na+

For element X represented above which of the following is the most likely explanation for the large difference between the second and third ionization energies

The Electron removed during the third ionization is, on average, much closer to the nucleus

Which of the following correctly compares periodic properties of two elements and provides an accurate explanation for that difference

The atomic radius of Cl is smaller that that of S because Cl has a larger nuclear charge than S does

The red line represents the lowest energy electron transition on this spectrum

True

As an atoms radius decreases

its ionization energy increases

A mixture of two gases 0.01 mol of C4H10(g) and 0.065 mol of O2(g) is pumped into a cylinder with a movable piston as shown above. The mixture originally at 200 C and 1.0 atm is sparked and the reaction represented below occurs. Which of the following is true after the project gases return to the original temperature and pressure and why will the change occur

the piston will be higher than its original position because the cylinder will contain a greater number of gas molecules

The average kinetic energy of the gas molecule is

the same in all three containers

Photons are pure energy not matter

true

Plants are green because they absorb red and blue wavelengths and reflect and transmit green wavelengths of light.

true

A 1.0 mol sample of He(g) at 25 C is mixed with a 1.0 mol sample of Xe(g) at 50 C. Which of the following correctly predicts the changes in average kinetic energy and the average speed of the Xe(g) atom that will occur as the mixture approaches thermal equilibrium

will decrease, will decrease