Exam 1, chapter 1-3 - Requires Respondus LockDown Browser + Webcam

Which of the following models of atom electron shells represents an atom that is most likely to form a cation with a charge of +1?

1 - 2 - 1

What is the concentration of hydroxide ions in a solution of pH 5?

10-9 M

Use the following figure to answer the question.Three moles of the compound in the figure would weigh how many grams? (Note: The atomic masses, in daltons (atomic mass units are equivalent to daltons), are approximately 12 for carbon, 1 for hydrogen.)

234

An ion that consists of 7 protons, 6 neutrons, and 11 electrons has a net charge of ________.

4-

Which of the following effects can occur because of the high surface tension of water?

A raft spider can walk across the surface of a small pond.

Which of the following best describes a controlled experiment?

An experiment includes at least two groups, one of which does not receive the experimental treatment

How does 0.5 M sucrose (molecular mass 342) solution compare to 0.5 M glucose (molecular mass 180) solution?

Both have 3.01 × 1023 molecules.

Nitrogen (N) is more electronegative than hydrogen (H). Which of the following is a correct statement about the atoms in ammonia (NH3)?

Each hydrogen atom has a partial positive charge; the nitrogen atom has a partial negative charge.

Which of the following are compounds?

H2O and CH4, but not O2

Which of the following statements is true for water in its liquid state?

It has a heat of vaporization higher than most other substances.

Which of the following is true of oxygen that has 8 protons, 8 neutrons, and 8 electrons?

It has an atomic number of 8.

If an atom has a charge of +1, which of the following must be true?

It has one more proton than it does electrons.

Which of the following is the quality of a good scientific hypothesis?

It should be testable in a valid period of time

Molybdenum has an atomic number of 42. Several common isotopes exist, with mass numbers from 92-100. Based on this information, which of the following is also true of molybdenum?

Molybdenum atoms can have between 50 and 58 neutrons.

A cell lacking which of the following structures is most likely to be a prokaryote?

Nuclear membrane

Following a scientific method, which of the following is the correct order of steps?

Observation → Hypothesis → Experiment → Analysis → Conclusion → Communicate results

Which answer best describes why ice floats in liquid water?

Stable hydrogen bonds keep water molecules of ice farther apart than water molecules of liquid water.

Why does a full bathtub have more thermal energy than a pot of freshly brewed coffee (even though the coffee has a higher temperature than the bathwater)?

The full bathtub has a greater volume

Use the information in the graph to answer the following question.

What is the impact of plowing soil on the number of earthworms?

All the organisms on your campus make up ________.

a community

Evolution is biology's overarching theme because evolution

all of the answers are correct - explains the unity and diversity of life - explains how organisms become adapted to their environment through differential reproductive success of varying individuals - explains why distantly related organisms sometimes resemble each other

Which of the following properties or processes do we associate with living things?

all of the answers are correct - reproduction - responding to the environment growth and development - evolutionary adaptations

Atoms have no electric charge because they have ________.

an equal number of protons and electrons

Which of the following types of cells use deoxyribonucleic acid (DNA) as their genetic material but do not have their DNA encased within a nuclear envelope?

archaean

To find out the number of neutrons in an atom, we need to know the following.

atomic mass and atomic number

How are the hydrogen bonds formed between water molecules?

by the attraction between the positive end of one water molecule with the negative end of the other

Which of the following properties of water is responsible for the formation of raindrops?

cohesion property

Which of the following best explain why argon, which is a noble gas, does not react with other elements. Noble gases ________.

have valence electron shells that are completely full

What kind of bonds are responsible for the unique cohesion, surface tension, and adhesion properties of water molecules?

hydrogen bonding

Which of the following types of bond is broken when water evaporates?

hydrogen bonds

Which of the following statements best distinguishes hypotheses from theories in science?

hypotheses are usually relatively narrow in scope, theories have broad explanatory power

As the [H+] of the solution decreases, the [OH-] ________.

increases and thus pH increases

Which of these provides evidence of the common ancestry of all living things?

near universality of the genetic code

Which of the following statements correctly describes the property of hydrophobic substances such as vegetable oil? Note that vegetable oil has lots of carbon atoms bound to hydrogen atoms and carbon and hydrogen have similar electronegativities.

nonpolar substances repel water molecules

A covalent bond is likely to be polar under which of the following conditions?

one of the atoms sharing electrons is more electronegative than the other atom

What is the pH of a solution with a hydroxyl ion [OH-] concentration of 10-12 M?

pH 2

What kind of bond is formed between the two hydrogen atoms and the single oxygen atom?

polar covalent bonds

Apple on tree ripens ripe apple produces ethylene ethylene signals neighboring apples to ripen neighbor apples produce more ethylene more apples ripen. The above process is an example of which of the following?

positive feedback regulation

In an experiment to test the hypothesis, "temperature controls sex determination in crocodile embryos" a researcher incubates crocodile eggs in incubators set at different temperatures. Which of the following correctly identifies the dependent and independent variables in the experiment?

sex is dependent, temperature is independent

When carbon dioxide in the atmosphere dissolves with the raindrops, what is the expected change in pH of the raindrops?

slightly acidic

To act as an effective coolant in a car's radiator, a substance has to have the capacity to absorb a great deal of heat. Which physical property is the best indicator for a good coolant?

specific heat

On a hot day, temperature of the sea rises more slowly than that of land. Which of the following statements best describe the process?

specific heat of soil is less than water

Which branch of biology is concerned with the naming and classifying of organisms?

taxonomy

Cotton-topped tamarins are small primates with tufts of long white hair on their heads. This is a heritable trait. While studying these creatures, researchers noticed that males with longer hair get more opportunities to mate. Which of the following research questions would best test the hypothesis that having longer hair improves mating opportunities?

test how many time males with shaved heads are mate compared to males with tufts

Which of the following has the smallest total mass?

two electrons