wileyplus hw questions exam 1

A laboratory room was reported to be 65.43 ft long. Since there are 12 inches in a foot and 2.54 cm in an inch, how many meters would you report for the length?

(65.43 ft) x (12 in/1 ft) x (2.54 cm/1 in) x (1 m/100 cm) = 19.943064 m = 19.94 m

In which numbers below the zeros are not significant numbers?(1) 0.0511 (2) 1.0020 (3) 1.00 x 10-3

1

Which of the following postulates from Dalton's atomic theory are now considered incorrect? I. All the atoms of a given element are identical. II. Matter consists of very small particles known as atoms. III. Atoms are indestructible and also indivisible.

1 and 3

What is the volume of a 66.7 gram sample of vanadium (density = 6.11 g/cm3)?

10.9 cm3

1657.3 grams of a compound are to be divided between 12 students. How many grams should each student receive? Express your answer with the correct number of significant figures.

138.11 g

the major isotopes of tungsten (with abundances shown) are 182W (26.32%), 183W (14.31%), 184W (30.67%), and 186W (28.62%). What is the atomic mass of tungsten?

182 x 26.32%/ 100= 183 x 14.31%/100= 184 x 30.67%/100= 186 x 28.62%/100= 184

A naturally occurring element consists of three isotopes. The data for the isotopes are: isotope 1: 46.972 u, 69.472% isotope 2: 48.961 u, 21.667% isotope 3: 49.954 u, 8.8610% What is the average atomic mass of this naturally occurring element?

1: (46.972 u/ 69.472%)/100= 32.63 2: (48.961 u/ 21.667%)/100= 10.61 3: (49.954 u/ 8.8610%)/100= 4.43 47.667 u

Which of the following statements is/are consistent with Dalton's atomic theory? I. The atoms in a given sample of an element do not share any common properties. II. Matter consists of particles called atoms. III. In chemical reactions, atoms merely rearrange, but do not disintegrate.

2 and 3

The number of significant figures in the reported value 0.002520 grams is

4

The atomic mass of naturally occurring iron, which is a mixture of isotopes, is listed as 55.847 u. This means that the average mass of iron is 55.847/12.011 times as great as that of a 12C atom 55.847 times as great as that of a 12C atom 55.847/1.0079 times as great as that of a 1H atom 55.847/12.000 times as great as that of a 12C atom 55.847 times as great as that of a 1H atom

55.847/12.000 times as great as that of a 12C atom

If I wanted to write the number 74,360 to three (3) significant figures, it would be 7.436 x 104 7.43 x 104 7.44 x 104 744 Answer you get not a choice

7.44 x 104

At my last physical examination, my doctor told me that my weight was 156 pounds and that my height was 5 feet 8 inches. I know both metric and metric-english conversions. You should know the former; as for the latter you can use 453.6 g = 1 pound (lb) and 2.54 cm = 1 inch. Thus, in metric units, the values above are

70.8 kg and 1.7 m

Dalton's atomic theory explains the law of conservation of mass and the law of definite proportions. Which of the following explain these laws? When atoms react, they break up and recombine to form new molecules. Atoms are indestructible. In chemical reactions, the atoms rearrange but they do not themselves break apart. When atoms of different elements combine to form compounds, new and more complex particles form. However, in a given compound the constituent atoms are always present in the same fixed numerical ratio. As atoms react, their properties change. When atoms combine to form compounds, they do so in order to attain simpler organization.

Atoms are indestructible. In chemical reactions, the atoms rearrange but they do not themselves break apart. When atoms of different elements combine to form compounds, new and more complex particles form. However, in a given compound the constituent atoms are always present in the same fixed numerical ratio.

Which of the following is consistent with the postulates from Dalton's atomic theory? Matter consists of tiny particles called ions. In chemical reactions, atoms not only rearrange, but also disintegrate in smaller subatomic particles. In a given chemical compound, the atoms can be present in various numerical ratios. The atoms in a given sample of an element are not necessarily identical. In a given chemical compound, the atoms are always present in the same fixed numerical ratio.

In a given chemical compound, the atoms are always present in the same fixed numerical ratio.

A compound of hydrogen and sulfur contains 2.69 grams of hydrogen and 47.31 grams of sulfur. Another sample of the same compound that contains 75.63 grams of sulfur would contain how many grams of hydrogen?

S= 47.31 grams H= 2.69g 2.69/46.31=x/75.63 =4.30 g

All of these statements describe properties of sodium. Which one describes a physical property of sodium? Sodium is never found as a pure metal in nature. Sodium is a solid at 25°C and changes to a liquid when heated to 98°C. Sodium's surface turns black when first exposed to air. When exposed to water, sodium reacts violently and a gas is formed. When placed in contact with chlorine, sodium forms a compound that melts at 801°C

Sodium is a solid at 25°C and changes to a liquid when heated to 98°C.

Charles' Law of gases says that the volume of a gas is proportional to its Kelvin temperature. If your laboratory thermometer read 37°C, what would this be in Kelvin?

The equation needed to convert °C to K is TK = (tC + 273 °C) (1K/1°C). Thus TK = (37 + 273 °C) (1K/1°C) = 310 K. 310 K.

Which of the laws of chemical combination is used to define the term compound? The law of conservation of mass. The law of definite proportions. The law of multiple proportions. None of these.

The law of definite proportions.

What is wrong with the following statement? "The atomic mass of an atom of chlorine is 35.453 u."

The mass 35.453 is the average atomic mass of an atom of chlorine.

Which answer below best describes all atoms of a particular element?

They possess the same number of electrons, the same atomic number, the same chemical properties, but not necessarily the same mass.

Which answer below best describes all atoms of a given isotope of a particular element? They possess the same number of electrons, the same atomic number, the same mass, but nothing else in common. They possess the same atomic number and the same mass, but have nothing else in common. They possess the same chemical properties and the same mass, but nothing else in common. They possess the same number of electrons, the same atomic number, the same mass, and the same chemical properties. They possess the same mass, only.

They possess the same number of electrons, the same atomic number, the same mass, and the same chemical properties.

All of these statements describe properties of tin. Which one describes a chemical property of tin? Tin can be hammered into a thin sheet. When a bar of tin is bent, it emits an audible "cry". The density of white tin is 7.365 g cm-3. Tin melts at 231.9°C. Tin dissolves slowly in cold, dilute hydrochloric acid, but it dissolves readily in concentrated hydrochloric acid.

Tin dissolves slowly in cold, dilute hydrochloric acid, but it dissolves readily in concentrated hydrochloric acid.

Which one of the following is a chemical change? When blue paint is mixed with yellow paint, a green colored paint is obtained. When blood is mixed with 3% hydrogen peroxide solution, it changes color. When water is boiled, it forms steam. When a solid stick of butter is heated, it becomes a liquid. When a bar of gold metal is pounded with a hammer, it flattens out.

When blood is mixed with 3% hydrogen peroxide solution, it changes color

When two different elements combine to form a chemical compound, they do so in_____________ proportions by mass.

When two different elements combine to form a chemical compound, they do so in definite proportions by mass.

In the movie Cool Hand Luke (1967) Luke wagers that he can eat 50 eggs in one hour. The prisoners and guards bet against him saying, "Fifty eggs gotta weigh a good six pounds. A man's gut can't hold that." A peeled, chewed chicken egg has a volume of approximately 53 mL. If Luke's stomach has a volume of 4.2 quarts, does he have any chance of winning the bet? Yes, because the volume of 50 eggs is about 0.94 qt. Yes, because the volume of 50 eggs is about 2.5 qt. No, because the volume of 50 eggs is greater than 4.2 qt. Yes, because the volume of 50 eggs is about 2.8 qt.

Yes, because the volume of 50 eggs is about 2.8 qt

Which is an example of an intensive property of matter?

color melting point

The relative number of atoms of each element in a particular compound? is the same as the weight ratio. is definite and constant. cannot be determined experimentally. is always 1:1. is the same as the density ratio.

is definite and constant.

The atomic number of silver, Ag, is 47 and it has an average atomic mass of 107.87. Why is it impossible to determine the number of neutrons in the nucleus of a silver atom?

it is not known which isotopes comprise silver, and the average atomic mass of an element depends on the weighted average of all isotopes of the element.

The force experienced by an object is its mass times its acceleration. What is the derived SI unit for force?

kg m/s2

What is the only SI base unit that includes a prefix?

kilogram (mass)

Each of the following properties of a sample of a pure substance can be used for identification except its solubility in water. melting point temperature. freezing point temperature. mass. density.

mass

atoms of 65Cu and 65Zn. Both of these atoms have the same

mass number

The atomic mass of naturally occurring gallium, which is a mixture of two isotopes, is listed as 69.723 u. This means that all gallium atoms found in nature have a mass which is 69.723/1.0079 times as great as that of a 1H atom. some gallium atoms found in nature have a mass which is 69.723/12.000 times as great as that of a 12C atom. some gallium atoms found in nature have a mass which is 69.723/1.0079 times as great as that of a 1H atom. no gallium atoms found in nature has a mass which is 69.723/12.000 times as great as that of a 12C atom. all gallium atoms found in nature have a mass which is 69.723/12.000 times as great as that of a 12C atom.

no gallium atoms found in nature has a mass which is 69.723/12.000 times as great as that of a 12C atom.

the different isotopes have different number of 2 isotopes differ in their

protons atomic mass

Which of the subatomic particles have roughly the same mass?

protons and neutrons

Why don't we count the electrons when determining the mass of an element?

the mass of the electrons is small

Which is an example of a chemical change? the separation of gases from liquids the separation of solids from liquids the separation of a mixture into its components the separation of air into oxygen, nitrogen, and other components the separation of a compound into its elements

the separation of a compound into its elements