A typical atom of Al has 13 electrons and 14 neutrons. How many protons does the atom have?

Suppose a neutral atom were to lose an electron. What would happen to the atom

Suppose a neutral atom were to lose an electron. What would happen to the atom

What is the atomic mass of this element?

A sodium atom can easily lose an electron. What happens to this electron?

Potassium has an atomic number of 19 and a mass number of 39. How many neutrons are in the nucleus of a typical potassium atom?

Which of the following represents a molecule?

When it rains, the combination of water and soil creates mud. Since the water and soil do not chemically combine, mud is considered to be

Before a chemical reaction, the total mass of the two reactants is measured to be 40 grams. After the reaction, what should the total mass of the products be?

The idea that matter is neither created nor destroyed is known as the

Hydrogen and oxygen react to produce water. which of the following is the correctly balanced chemical equation for this reaction?

The first part of a balanced equation is shown Cu+ 2AgNO₃ ---> _________. In order for this equation to be balanced, how many oxygen atoms must be present in the products?

In which state of matter would the molecules be farthest apart?

Metals are commonly used in medical implants, but they have the disadvantage of tending to corrode. When a metal corrodes, the metal is worn away or gradually destroyed.

Which of these is the most likely solution for preventing metal corrosion when metal is used in the human body?

Students were studying the first 20 elements on the periodic table. One student found a diagram of a silicon nucleus. In the diagram the large circle represents the nucleus. The rest of the particles are represented as shown in the key. Based on the diagram and the periodic table, which three statements correctly describe a silicon atom?

A student was reading about the gases in air. Ozone helps protect Earth from harmful ultraviolet rays that come from the sun. Certain types of pollution created by humans have caused a hole in the ozone layer. This hole is over the South Pole and could become larger if this type of pollution increases.

Which question should the student ask to determine if ozone is an elemental molecule?

The table shows the estimated percent concentrations of atmospheric gases. Trace gases are composed of small amounts of gases such as carbon dioxide, water vapor, and methane. Which of these will most likely increase the amount of a trace gas in the

atmosphere?

Which diagram correctly represents the mass of one of the chemical reactions?

Which statement correctly describes how matter is conserved in a Chemical Reaction?

Coal is mostly carbon. When coal is burned, it reacts with oxygen. The carbon dioxide produced is released into the atmosphere. The chemical reaction for coal burning is shown.

C + O2 → CO2

Based on the model shown, which statement correctly describes what

may happen to the carbon dioxide in the atmosphere?

A student has been learning about atoms. He wrote a small paragraph describing one.

How an Atom Looks

An atom looks similar to a racetrack. There are small particles that move like cars on a racetrack. These particles move in a circle around the center of the track and do not easily move away from the center.

The student describes particles on the edge of the atom. Which statement supports the student’s claim that the particles on the edge of the atom do not move away from the center?

Students have been studying air quality. The teacher provides them with particle diagrams of the components of five air samples.

Which three diagrams contain compound molecules?

Students make lists of characteristics that describe an isotope of carbon (C). Which list is correct?

Which statement best classifies air?

Students compare the properties of the substances in Table 3 with the properties of the elements in Table 4.

Which conclusion is best supported by the information?

Students are studying the behavior of matter as a gas. Each sample is at the same temperature and in different 1.0-liter rigid containers. The number of particles shown in the diagram is proportional to the number of particles in each sample. Which three statements about the gas in the containers are true?

Students were looking at coins during lunch. One of them noticed that older pennies looked and felt different from new pennies. The students decided to investigate whether all pennies are made of the same materials. The students measured the mass and the volume of 10 pennies and then divided the mass by the volume to determine the density. The measurements were recorded in a data table. The teacher told the students that newer pennies contain copper and zinc. Copper has a density of 8.96 g/cm3. Zinc has a density of 7.1 g/cm3.

Which statement is best supported by the data and information from the

teacher?

Which is not a result of acid rain?

Scientists issue an alert about harmful high levels of ozone. What level of the atmosphere are they concerned about?

Which of the following correctly describes the greenhouse effect?

Which of the following is a valid method for reducing the amount of greenhouse gases in the atmosphere?

NASA scientists have studied the ozone concentration of the air above Antartica over a period of years. This information is represented in the graph.Which would explain the data in the graph?

A student was reading about the gases in air. Ozone helps protect Earth from harmful ultraviolet rays that come from the sun. Certain types of pollution created by humans have caused a hole in the ozone layer. This hole is over the South Pole and could become larger if this type of pollution increases.

Which question should the student ask to determine if ozone is an elemental molecule?

The table shows the estimated percent concentrations of atmospheric gases. Trace gases are composed of small amounts of gases such as carbon dioxide, water vapor, and methane. Which of these will most likely increase the amount of a trace gas in the

atmosphere?

A Tennessee student studying the carbon cycle learned that carbon moves through all four spheres of Earth: the atmosphere, the hydrosphere, the biosphere, and the geosphere. The student wanted to understand how carbon cycles through both the abiotic and biotic parts of the planet.

The student knew that limestone, the official state rock of Tennessee, contains carbon because it is made of calcium carbonate (CaCO3). The student learned that the water (H2O) in the ocean absorbs carbon dioxide (CO2) from the atmosphere. This produces carbonic acid (H2CO3), which easily splits apart into +− hydrogen ions (H ) and bicarbonate ions (HCO3 ), which are both charged particles. The chemical reaction for this process is shown. The bicarbonate ions (HCO3 ) split into more hydrogen ions (H ) and carbonate ions (CO32−). Corals and mollusks pull in seawater that contains the carbonate ions and

2+calcium ions (Ca ) and pump out any hydrogen ions. The organisms use the carbonate and calcium ions to make calcium carbonate (CaCO3) for their skeletons and shells.

When the corals and mollusks die, layers of their skeletons and shells form on the ocean floor. As the layers are buried by sediments, they compact and cement to form

limestone, which is a sedimentary rock made of calcium carbonate (CaCO3). Which step in the formation of limestone includes biotic parts of the system?

After learning about limestone formation in a marine environment, the student was still curious about the cycling of carbon through the biotic and abiotic parts of the planet in a terrestrial environment. The student found a diagram on the website that shows another way that carbon in the atmosphere is absorbed into another part of the planet. This diagram shows the carbon moving directly into the biosphere. The student learned that plants absorb carbon dioxide from the atmosphere and use it for photosynthesis. During photosynthesis, plants make sugars that are used by the plant for growth and that are stored for energy. Animals eat the plants for food and absorb the carbon in the sugar. When the plants and animals die, their bodies decay, releasing carbon into the soil. Under the right conditions, decaying plants can turn into coal, which is almost pure carbon. Eastern Tennessee has several coal mines that produce tons of coal each year. This coal is burned for energy, which releases carbon dioxide back into the atmosphere. Coal is mostly carbon. When coal is burned, it reacts with oxygen. The carbon dioxide produced is released into the atmosphere. The chemical reaction for coal burning is shown.

C + O2 → CO2

Based on the model shown, which statement correctly describes what may happen to the carbon dioxide in the atmosphere?

The student learns that carbon dioxide is stored in Earth’s mantle. Which part of the carbon cycle diagram shows the carbon dioxide from the mantle being cycled to another sphere of Earth?

One of the components contained in gasoline is octane C8H18 . Which () statement best describes C8H18?

The diagram represents solar panels collecting energy from sunlight and then converting that energy to electrical energy. The electrical energy can be stored as chemical energy in batteries. Then, this chemical energy can be converted back to electrical energy to power lights and appliances. Which of these best describes a similarity between photosynthesis and the changes in energy represented by the diagram?

Coal is mostly carbon. When coal is burned, it reacts with oxygen. The carbon dioxide produced is released into the atmosphere. The chemical reaction for coal burning is shown.

C + O2 → CO2

Based on the model shown, which statement correctly describes what

may happen to the carbon dioxide in the atmosphere?

Certain antibiotics are no longer effective against the bacteria that they used to kill. How might this be explained?

A scientist studying the effects of radiation on DNA performs an experiment in which she exposes a sequence of nitrogen bases found in DNA to radiation. The DNA before and after the radiation is shown below. Use the evidence to determine whether a mutation has occurred, and if so, interpret that mutation. Before Exposure: ATCGTCA; After Exposure: ATTCGTCAA.

Which organism supports the the organisms by making food from the nonliving components in the ecosystem?

Scientists change genes of a tomato plant to produce a protein that is a natural pesticide. Justify why this is classified as a positive mutation.

The hydra is an animal that lives in freshwater streams and ponds. It reproduces by producing eggs and also by budding, a form of asexual reproduction. What advantage does budding give hydra?

The front leg of a cat, the front flipper of a dolphin, and the wing of a bat have the same structure and order of bones. These structures do not look alike and are not used in the same way, but their bones are similar. What might scientists say about the cat, dolphin, and bat based on this evidence?

In a particular breed of cattle, the trait of not having horns (Pp) is dominant over having horns (pp). The Punnett square below shows a cross between parents with Pp and pp genotype.

What percentage of offspring will be without horns?

Information about dairy products, lactose, and lactase are listed in the table shown. Based on this information, which hypothesis best predicts how a change

to the gene could affect people who do not produce enough lactase?

A partial food web shows the movement of matter and energy in a land ecosystem. Deer need producers and oxygen to provide energy and matter for their cells. What is the primary source of oxygen for the deer in this ecosystem?

White-tailed deer are mammals. Mammals have a reproductive strategy that is not found in all animals.

Which two statements provide a cause and effect of the reproductive strategy of white-tailed deer that helps them survive?

The photograph shows a two-toed sloth. These slow-moving organisms cannot outrun or outclimb predators, so they spend most of their time hanging from branches in trees. The sloths eat the leaves and flowers from these trees. Two-toed sloths often have a greenish tint on their fur because algae grow on their bodies. Which of these is the most likely reason the algae are able to help two-toed sloths survive?

Almonds are edible seeds that grow on trees. Wild almonds typically have a bitter taste caused by a chemical in the almond. If an organism eats wild almonds, a chemical reaction occurs that releases the bitter taste. However, a genetic mutation in the almond tree can occur that prevents wild almonds from producing the bitter taste. Which statement describes how this type of mutation could affect these wild almond trees?

What function do these models serve to better understand the difference between a prokaryotic cell and an eukaryotic cell?

What information could this scientific model provide people about a prokaryotic cell?

In the diagram, which cell structure is responsible for taking in and breaking down foreign particles and damaged organelles?

The structure labeled X is found in both amoeba and plant cells. What is the name of this structure?

What is the name of the cell part that contains structures 1 and 2?

Which cellular structure makes protein and is present in all three cells?

Students look at pictures of structures found in living organisms. Each picture represents a different level of complexity. Which sequence places the structures in order from least complex to most complex?

Protists are organisms that are classified in their own kingdom. Protists are not plants or animals, yet some protists have characteristics similar to those of either plants or animals or both. A protist like the protozoan shown in the picture has similarities to both plants and animals. This protozoan is similar to animals because it has the ability to move from place to place while obtaining nutrients. This protozoan also shares a similarity with plants. Which feature labeled on the protozoan is associated with organisms in the plant kingdom but not in other kingdoms except protists?

A student investigates the process of passive transport by the cell membrane by creating a model. The student puts a starch solution in a dialysis tubing bag. The bag is then placed in a beaker that contains an iodine solution. The dialysis tubing bag is semipermeable. The student’s observations are in the table. The student concludes that the iodine passes through the dialysis tubing material but the starch molecules cannot.

Which two statements provide evidence to support the student’s

conclusion?

The diagram represents a cellular process used by cells. In which situation would this process be beneficial to the cells?

A person riding a bicycle wants to move the bicycle forward. She moves her legs up and down on the bicycle’s pedals. Then the rider wants to stop the bicycle. She stops pedaling and the bicycle slows. She takes one of her feet off a pedal and puts her foot on the ground to stop the bicycle and stay upright.

Which of these best identifies a pathway of systems in the rider’s body, as described in this scenario?

A student uses a microscope to observe a single-celled organism that can move. The organism contains a nucleus and many chloroplasts. Based on the observations, the student claims the organism is not a bacterium. Which observation best supports the student’s claim?

When an athlete began running, both her breathing and heart rates increased.

The athlete’s breathing and heart rates increased as she was running because the athlete needed to

Damaged cells can release chemicals known as growth factors. Some of these growth factors can cause nearby cells to divide.

Which pair identifies the process used by the nearby cells to divide and the result of that process?

Meiosis is a special type of cell division that reduces the number of chromosomes by half. Four haploid cells known as sex cells are created during this process. Meiosis occurs in all sexually reproducing organisms including animals, plants, and fungi. Sex cells are produced for the purpose of creating new offspring. Not all organisms reproduce sexually, but those that do experience increased genetic diversity in their populations. The parent cell in Figure 2 already contains double the amount of original genetic material. Which event must have occurred before the parent cell in Figure 2?

Mitosis occurs in the organelle that controls cell activities. Which organelle should be added to the model in Figure 1 to show where this process is occurring?