Science Midterm

50 meters per minute

A bird flew 100 meters in 2 minutes. What was the bird's speed?

3 hours

A car traveling 65 kilometers per hour travels 195 kilometers. How long did it take the car to travel that distance at that speed?

17 mph

A dolphin keeps up with a boat for a distance of 51 miles for 3 hours. What is the dolphin's average speed?

100 mph south

A motorcycle travels 300 miles south in 3 hours. What is the average velocity?

Chemical Reaction(1)

A process that leads to the transformation of one set of chemical substances to another.

16 mph

A racehorse wins the 3200 meter cup in a time of 200 seconds. What is the racehorse's average speed?

A) 6H₂O

A water molecule is made up of two Hydrogen (H) atoms and one oxygen (O) atom. In a chemical equation, what would be the correct way to represent six water molecules? A) 6H₂O B) 6HO₂ C) 2H₆O₆ D) 12H₆O

885 kph west

An airplane travels 4,425 kilometers west in 5 hours. What is its average velocity?

A) Observation I

An experiment is performed in which a crystalline substance is added to a beaker filled with room temperature water. The following observations are made: I. The crystals dissolve II. A precipitate is formed III. The bottom of the beaker feels warm to the touch IV. Bubbles begin forming within the water All of the observations are evidence of a chemical change EXCEPT- A) Observation I B) Observation II C) Observation III D) Observation IV

Substance

Elements or compounds that can only be separated or combined to make substances with new properties by means of a chemical reaction

Balanced equations are equations showing a chemical reaction. The law of conservation of mass states that mass cannot be created of destroyed. In a balanced equation there are two parts, the reactants and the products. These parts have the chemical formulas that shows what elements are in the reaction. In a balanced equation you can count up the number of element in the reactant and the number of elements in the product and it will be equal.

How are chemical formulas and balanced equations used to demonstrate conservation of mass?

D) 8

How many atoms of Hydrogen (H) are found in this substance? (NH₄)₂CO₃ A) 2 B) 4 C) 6 D) 8

2 hours

How much time does it take a person to walk 8 kilometers east at a velocity of 4 kilometers per hour?

14 m/s

If a car goes from 0 mph to 70 mph in 5 seconds, what is its acceleration?

17,600 mph

If a rocket travels 35,200 miles in 2 hours, what is its speed?

22.5 kilometers

If the velocity of a car is 45 kilometers per hour west, how far can it travel in 0.5 hours?

18 meters per second north

If you are on a bus traveling 20 meters per second north, and you get up and move to the back of the bus at a speed of 2 meters per second south; What is your velocity?

22 Meters per second north

If you are on a bus traveling 20 meters per second north, and you get up and move to the front of the bus moving at a speed of 2 meters per second north; What is your velocity?

B) Subscript

In a chemical formula, what is used to indicate the number of atoms of each element? A) Atomic Number B) Subscript C) Coefficient D) Atomic Mass Number

D) 1

In an experiment, two flasks of unknown, clear liquids are combined in a beaker and the following observations are obtained: - Solution color remains clear - The amount of solution in the beaker increased - The solution temperature changed from 10 C to 20 C. - Some of the liquid remained in the flasks. How many of the listed observations indicate a new substance was formed? A) 4 B) 3 C) 2 D) 1

A) After putting liquid batter into a hot pan, the batter solidifies and begins to turn brown.

In which of the following examples has a chemical reaction occurred? A) After putting liquid batter into a hot pan, the batter solidifies and begins to turn brown. B) After turning on a blender filled with fruits, the fruit is chopped up and mixed together. C) After taking a tray filled with ice cubes out of the freezer, the ice cubes begin to melt. D) After adding a spoonful of sugar to a mug of hot coffee, the sugar dissolves completely.

B) Water

Mrs. Davis has asked Kyle to retrieve a compound from the chemical cabinet. Which of the following should Kyle retrieve? A) Oxygen B) Water C) Chlorine D) Aluminum

Motion

Occurs when an object changes position relative to a reference point.

Subscript

Representation of the number of atoms of an element in a molecule.

A) 4

The chemical formula for a certain substance is shown here. How many different elements are present in the substance represented by the chemical formula shown? Be₃AI₂(SiO₃)₆ A) 4 B) 7 C) 15 D) 29

Velocity

The distance an object travels in a specific amount of time, along with the object's direction.

Speed

The distance an object travels in a specific amount of time.

Chemical Formula

The number of atoms and molecules that make up the reactants and products of a chemical reaction.

Acceleration

The rate at which Velocity changes

Coefficient

The representation of the number of molecules in a reaction.

4,452 meters

The speed of sound in air is roughly 1,484 m/s. How far, in meters, would a sound wave travel in 3 seconds.

Products

The substance that is yielded from a chemical reaction.

Reactants

The substances initially involved in a chemical reaction.

Law of Conservation of Mass

The total number of atoms of each element is not changed during a chemical reaction.

False, It can also mean slowing down

True or False? Acceleration only means speeding up.

B) A substance that is made up of more than one kind of atom

Water is an example of a compound. Which of the following is the best description of all compounds? A) A substance that cannot be broken down into simpler substances B) A substance that is made up of more than one kind of atom C) A material that has a specific density at a specific temperature D) A group of atoms that have different abilities when joined together

Graphs

What are often used to display speed?

change in speed, direction, or both

What could acceleration be?

Velocity/Time

What is the formula for Acceleration?

Distance/Time = Speed

What is the formula for speed?

28 kph north

What is the velocity of a rocket that goes 700 kilometers north in 25 seconds?

Chemical Reaction(2)

When atoms of substances rearrange themselves into a new configuration.

B) Show that a gas is forming

When vinegar and baking soda are combined, bubbles begin to form. Bubbles are evidence of a chemical reaction because they-- A) Pop when they are touched B) Show that gas is forming C) Form at a fast rate D) Are generally transparent

D) N: 1 H: 4 C: 1 O: 3

Which of the following correctly identifies the number of each element involved in the chemical formulas? NH₄CO₃ A) N: 4 H: 4 C: 3 O: 3 B) N: 1 H: 1 C: 1 O: 3 C) N: 0 H: 4 C: 0 O: 3 D) N: 1 H: 4 C: 1 O: 3

C) Bleach gets rid of a ketchup stain on a white shirt

Which of the following examples shows that a chemical reaction has occurred? A) Teeth chop up an apple slice into smaller pieces. B) Sugar placed in sugar water sinks to the bottom. C) Bleach gets rid of a ketchup stain on a white shirt. D) A glass jar shatters into many pieces when dropped.