A chemist measures the mass of an unknown substance. The mass is 2.53 g. Which statement best describes the chemist’s measurement?

(1 point)
It is a qualitative inference.
It is a quantitative inference.
It is a qualitative observation.
It is a quantitative observation.Which of the following is a set of units from the International System of Units (SI)?
(1 point)
gram (g); ounce (oz); meter (m)
kilogram (kg); liter (L); kilometer (km)
pound (lb); liter (L); inch (in.)
pound (lb); ounce (oz); foot (ft)

3.
A student is carrying out a chemistry experiment in the laboratory. The student is wearing a white lab coat, plastic goggles, latex gloves, and sandals. How can the student best improve laboratory safety?
(1 point)
put on closed-toed shoes
use cloth gloves instead of latex
put on a darker-colored lab coat
use glass goggles instead of plastic

4.
Which statement explains how oceans affect the biomes in an area?
(1 point)
Ocean currents always make biomes near the oceans warmer.
Biomes near the ocean are much windier than biomes in other areas.
Ocean currents take moisture away from biomes located near oceans.
Biomes near the ocean have less variation in day and night temperature.

5.
In an ecosystem, a tree takes in energy from the sun to make fruit. An animal eats the fruit except for the peel. Bacteria breaks down the peel into soil. Which of the following accurately describes the role of each organism in this ecosystem?
(1 point)
tree: prey
animal: decomposer
bacteria: predator
tree: producer
animal: scavenger
bacteria: herbivore
tree: omnivore
animal: carnivore
bacteria: scavenger
tree: producer
animal: consumer
bacteria: decomposer

6.
Which of the following statements describes the process of evaporation in the water cycle?
(1 point)
Water melts from a glacier and flows down a mountain into a lake.
Water is heated and moves from the ocean into the atmosphere.
Moisture in air cools and gathers, forming water droplets in the air.
Rain falls from clouds to the ground and is absorbed as groundwater.

7.
Which process removes carbon dioxide from the atmosphere?
(1 point)
respiration
decomposition
photosynthesis
metamorphosis

8.
Which effect could happen as a result of eutrophication caused by runoff from a farm field?
(1 point)
a decrease in organic nutrients in a lake
a loss of oxygen in an aquatic ecosystem
an increase in biodiversity near a river delta
a gain in sunlight availability in a pond ecosystem

9.
Which observation would best support the theory of global warming?
(1 point)
A region has received a decrease in total rainfall over the past three years.
The average surface temperature of Earth has risen over the last 100 years.
The average annual temperature across a region has risen for two years in a row.
This year’s highest temperature on Earth is warmer than last year’s highest temperature.

10.
Precious metals are mined from Earth’s crust to make many things like electronics or medical equipment. Which sphere of the Earth system contains precious metals that can be mined?
(1 point)
atmosphere
biosphere
geosphere
hydrosphere

11.
Which property of Earth is most important for life to exist on the planet?
(1 point)
It has liquid water.
It rotates on its axis.
It has day and night cycles.
It contains hydrogen and oxygen.

12.
The strength of gravity between two objects depends on which factors?
(1 point)
speed and time
speed and mass
distance and time
mass and distance

13.
Which statement describes the fall equinox in the Northern Hemisphere?
(1 point)
Both hemispheres are tilted toward the sun.
Neither hemisphere is tilted toward the sun.
The Southern Hemisphere is tilted toward the sun.
The Northern Hemisphere is tilted toward the sun.

14.
Why is the moon visible from Earth?
(1 point)
The part of the moon facing Earth reflects light back to Earth.
The half of the moon facing the sun reflects light toward Earth.
Half of the moon produces light and some travels toward Earth.oward Earth.
oward Earth.
The part of the moon that produces light changes as it orbits Earth.

15.
How does high tide change with the motion of the moon?
(1 point)
High tide rotates in the opposite direction as the moon.
High tide appears at night and disappears during the day.
High tide appears during the day and disappears at night.
High tide rotates to remain directly in line with the moon.

16.
Which pairs of planets are characterized correctly as terrestrial planets and gas giants?
(1 point)
Terrestrial: Venus and Saturn
Gas Giants: Mars and Neptune
Terrestrial: Uranus and Earth
Gas Giants: Mercury and Saturn
Terrestrial: Venus and Mars
Gas Giants: Jupiter and Neptune
Terrestrial: Mercury and Jupiter
Gas Giants: Venus and Uranus

17.
Which element undergoes nuclear fusion in the sun’s interior to create most of the sun’s energy?
(1 point)
carbon
helium
hydrogen
oxygen

18.
Which of the following best describes the planet Uranus?
(1 point)
an inner planet with a very thick atmosphere and an extremely hot rocky surface
a blue-green gas giant that rotates from top to bottom rather than from side to side
a red planet with a surface rich with iron that has a thin atmosphere of mainly carbon dioxide
the largest and most massive planet with a thick atmosphere made of mainly hydrogen and helium

19.
Which shows the correct sequence for the life of a star that is more massive than the sun?
(1 point)
nebula > main sequence star > protostar > supernova > red giant
main sequence star > red giant > nebula > protostar > supernova
protostar > supernova > red giant > nebula > main sequence star
nebula > protostar > main sequence star > red giant > supernova

20.
The Big Bang Theory states that
(1 point)
the universe is expanding.
the universe is heating up.
the universe is contracting.
the universe is cooling down.