Albert Einstein
Which substance is a mixture? sugar/ salt/ water/ milk
What is milk
A.Sugar dissolving in water
B.Fire burning paper
C.Souring milk
D.Rusting metal
What is sugar dissolving water
If we wanted to separate metal shards from water what are two things we can use
What is filter and magnet
The distillation apparatus separates components of a mixture based on
a. The color
b. The Boiling Point
C. The teacher
D. The liquid it has
What is B, the Boiling Point
When 5 g of solid zinc is placed into a beaker that holds 15 g of a hydrochloric acid solution, bubbles of hydrogen form.The mass of the contents of the beaker after the reaction is less than 20 g. Which statement BEST explains the difference in mass?
A. The solid zinc reacted, so some of its mass was lost during the reaction
B. The solid zinc did not react completely, so not all of the at yy oms of reactants could become part of the products.
C. It is expected because some atoms are used up in each chemical reaction.
D. The lower mass is a result of the hydrogen gas leaving the beaker
D. The lower mass is a result of the hydrogen gas leaving the beaker
A law that states that the total mass of the substances before a chemical change is the same as the total mass of the substances after the chemical change.
What is law of conservation of mass
which of these represents a chemical change?
A. a match is lit, creating a yellow-orange flame
B. a small pie e of ice melts, changing from a solid to a liquid
C. a ball of clay sinks in water, and floats when reshaped.
D. a pot of water is heated to boiling, and evaporation occurs
What is A. a match is lit, creating a yellow-orange flame
A mixture in which two or more pure substances are not evenly mixed
what is Heterogeneous Mixture
A mixture in which two or more pure substances are evenly mixed.
What is Homogeneous Mixture
which statement best describes a physical change?
A. a process separates water into hydrogen gas and oxygen gas
B. an iron nail exposed to the atmosphere forms rust.
C. burning carbon releases the gas carbon dioxide. D. salt added to a cup of water makes salt water.
What is D. salt added to a cup of water makes salt water.
The students calculated the total mass of the original solutions to be 195.7 grams. The mass of the solution was 186.2 grams. What is the law of the conservation of mass AND assuming the data is correct, why does this chemical reaction not violate the law?
The Law of Conservation of mass states the total mass of the substances before a chemical change is the same total mass after the chemical change.
a student stirs together salt crystals and sugar crystals. the crystals are the same size and color. together the salt and sugar make a ...
solution/ compound/ mixture/ molecule
What is mixture
which process most likely produces a physical change, without a chemical change? A. a solid is exposed to heat and transforms into a liquid B. two liquids are mixed together and a solid forms in the solution C. a metal burns in air and produces a white powder D. a metal is exposed to water and becomes corroded
What is A. a solid is exposed to heat and transforms into a liquid
a student observes that a gas if formed when chemical Y is added to chemical Z in the lab. The student's observation of a new product being formed is the common outcome of all __________ changes. physical/ chemical/ mass/ phase
What is chemical
In distillation, the mixture is heated until the pure substance with the lowest boiling point changes to a gas. This gas is typically condensed back into a _______________
what is a liquid
a combination of salt and sugar grains is best classified as a mixture because...
A. the grains taste different from one another
B. both the salt and sugar grains are in the same state of matter
C. no new chemical bonds are formed between the salt and sugar grains
D. a new product is formed when the salt and sugar grains are combined.
What is C. no new chemical bonds are formed between the salt and sugar grains
a student applies heat to a solid substance. which indicates that a chemical change occurred?
A. the substance becomes a liquid but solidifies when cooled
B. the substance changes color and stays that color when cooled
C. the substance goes from liquid to gas very quickly D. the substance expands but stays the same color
What is B. the substance changes color and stays that color when cooled
From the choices below, what are two different ways to separate a Heterogeneous Mixture?
A.Filtering
B.Distillation
C.Grabbing
D.Mixing
What is Filtering and Distillation
A tea bag put in a cup of hot water is an example of what
a. Evaporation
b. Filtration
C. Distillation
D. Condensation
What is b. Filtration because liquid materials pass through the bag but solid materials do not.
A scientist decided to use hydrochloric acid to test a piece of metal to and evidence that it was the element zinc, which undergoes a chemical reaction with hydrochloric acid. What evidence would indicate to a scientist that a chemical reaction had occurred? Select THREE correct answers.
A. change in the temperature of the solution
B. decrease in the mass of the solution
C. bubbling of the solution
D. no visible change to the solution
A, B, and C
a science teacher demonstrated physical and chemical changes by using a fork to hold a marshmallow over alit candle. which observation is the best evidence of a chemical change?
A. some candle wax melted
B. metal in the fork became warmer
C. the marshmallow became sticky on the inside
D. the marshmallow developed a brown crust on the outside
What is D. the marshmallow developed a brown crust on the outside
a strip of magnesium burns at a temperature of about 2220C. burning magnesium produces a brilliant white light and leaves behind a white powder known as magnesium oxide. which best explains why the burning of magnesium results in a chemical reaction?
A. a new substance is formed
B. a temperature increase occurred
C. the appearance of the magnesium strip changed. D. the state of matter of the magnesium strip changed
What is A. a new substance is formed
a student observes actions that occurred in four different eggs. which action describes only a chemical change?
A. cut up egg
B. stirred egg
C. rotting egg
D. dropped egg
What is C. rotting egg