Chemistry- (Unit 1) Cumulative Review

The following balanced equation shows the formation of sulfur dioxide. S + O2 > SO2 How many moles of sulfur are needed to produce 15.0 mol of sulfur dioxide? 7.50 mol 10.5 mol 15.0 mol 30.0 mol

15.0 mol

Nitrogen dioxide, a major air pollutant, can be produced by the combustion of nitrogen oxide as shown. 2NO + O2 > 2NO2 In a plant, 1,500 kg of nitrogen oxide is consumed per day to produce 1,500 kg of nitrogen dioxide per day. What is the percent yield?Use: % yield= (actual yield/theoretical yield) x100 21.7% 32.6% 43.5% 65.2%

65.2%

What was Johann Dobereiner's contribution to the development of the periodic table? He arranged the elements according to increasing atomic mass. He arranged the elements according to increasing atomic number. He identified triads of elements that had similar properties. He organized elements into four groups based on their properties.

He identified triads of elements that had similar properties.

Which of the following observations would indicate that a material is a pure substance? It does not dissolve in water. It changes color after heating. It cannot be physically broken down into different types of atoms. It can be physically broken down into different types of molecules.

It cannot be physically broken down into different types of atoms.

Which property would xenon most likely have? It is stable. It is a solid. It is flammable. It is silver in color.

It is stable.

Which is most likely true about electronegativity? It tends to be the same across a period. It tends to be the same down a group. It tends to increase across a period. It tends to increase down a group.

It tends to increase across a period.

The volume of a gas decreases to half of its original volume, but the gas maintains the same number of moles and temperature. According to the ideal gas law, what will most likely happen to the pressure? It will double. It will decrease. It will increase slightly. It will remain the same.

It will double.

Which compound most likely contains polar covalent bonds? NaCl AlF3 Br2 NF3

NF3

Why do amorphous solids not have a long-range order in the arrangement of their particles? Their formation involves very rapid cooling. They do not have enough particles. Their particles eventually change positions. Their particles always stay in the same positions.

Their formation involves very rapid cooling.

Which statement about hydrogen bonds is true? They are the only force that allows a gecko to climb up glass. They are the weakest of the intermolecular forces. They are much stronger than intramolecular forces. They help water striders walk on water by creating surface tension.

They help water striders walk on water by creating surface tension.

Which best characterizes a crystal? a number of high speed particles moving randomly a dense substance that is hard and incompressible a high-energy state of matter made up of a swirling, ionized gas a loose association of particles moving past one another

a dense substance that is hard and incompressible

Which commercial technology commonly uses plasmas? a radio a race car a television a microwave oven

a television

Which word equation shows lithium oxide being formed from the reaction between oxygen and lithium? oxygen + lithium oxide > lithium lithium + oxygen > lithium oxide oxygen + lithium > lithium + oxide lithium oxide > lithium + oxygen

lithium + oxygen lithium oxide

Sodium combines with water to produce sodium hydroxide and hydrogen gas. Which word equation represents this violent reaction? sodium hydroxide + water > sodium + hydrogen sodium + water > sodium hydroxide + hydrogen sodium + hydrogen > sodium hydroxide + water sodium + sodium hydroxide > water + hydrogen

sodium + water > sodium hydroxide + hydrogen

A tire at 21°C has a pressure of 0.82 atm. Its temperature decreases to -3.5°C. If there is no volume change in the tire, what is the pressure after the temperature change? Use: P1/T1=P2/T2 0.75 atm 0.89 atm 1.1 atm 1.3 atm

0.75 atm

The molar mass of water (H2O) is 18.0 g/mol. A sample of water has a mass of 18.0 g. How many moles of water are contained in this sample? 1.00 18.0 36.0 324

1.00

The chemical equation below shows the decomposition of ammonium nitrate (NH4NO3).NH4NO3 N2O + 2H2OA chemist who is performing this reaction starts with 160.1 g of NH4NO3. The molar mass of NH4NO3 is 80.03 g/mol; the molar mass of water (H2O) is 18.01 g/mol. What mass, in grams, of H2O is produced? 9.01 18.01 36.03 72.06

72.06

Which law is described by saying that when the pressure of a gas in a sealed container is cut in half, the gas will double in volume at a steady temperature? Boyle's law Charles's law Dalton's law Gay-Lussac's law

Boyle's law

Which is an aspect of the kinetic-molecular theory and can be used to explain the compressibility of plasmas? Particles move independently of one another and are widely spaced. Particle kinetic energy increases with increasing temperature. Particles exert no attractive or repulsive force on one another. Particles always move even when they have fixed positions.

Particles move independently of one another and are widely spaced.

Which statement describes heterogeneous mixtures? They are made up of two or more pure substances that are not chemically bonded together and appear non-uniform. The substances they are composed of can only be separated chemically. The substances they are composed of have fixed ratios between their components. They are made up of two or more pure substances that are chemically bonded together and appear uniform.

They are made up of two or more pure substances that are not chemically bonded together and appear non-uniform.

Which statement describes the electron sea model for metallic bonding? This model involves electrons held tightly between atoms. This model explains all properties of metals. This model involves electrons moving among bands of orbitals. This model is the simplest model.

This model is the simplest model.

Which proportionality shows the result of combining Avogadro's law with Boyle's law? V - 1/nP V - n/P V - P/n V - nP

V - n/P

A scientist is examining a mixture of nitrogen, hydrogen, and ammonia. The individual pressures that are exerted by nitrogen and hydrogen are 0.26 atm and 0.28 atm, respectively. If the total pressure is 0.90 atm, what is the partial pressure of ammonia?Use PT+P1+P2+P3+...+Pn 0.27 atm 0.36 atm 0.54 atm 0.90 atm

0.36 atm

The table below gives the data that is needed to calculate the average atomic mass of element B. Based on these data, what is the average atomic mass of element B? 10.01 10.51 10.81 11.01

10.81

What did J. J. Thomson observe when he applied electric voltage to a cathode ray tube in his famous experiment? The stream of cathode ray particles was moving very slowly. The glass opposite of the negative electrode started to glow. The electric voltage had little effect on the stream of particles. The tube contained two pieces of metal that served as electrodes.

The glass opposite of the negative electrode started to glow.