2nd 6 wks 3 Week Review

PowerPoint by: Katherine PeaseQuestions by: Rebecca Neill

1. Steel wool in Jar A rusts and the steel wool in Jar B does not rust. What is the manipulated variable that best explains the difference?

Answer:

• Exposed to air and Exposed to air and water, one is notwater, one is not

• Manipulated Variable is Manipulated Variable is the lidthe lid

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2. What evidence supports 2. What evidence supports that a chemical change that a chemical change takes place when rusting takes place when rusting occurs?occurs?

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answer

• Color changeColor change

• Change in chemical Change in chemical makeupmakeup

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3. What type of 3. What type of property is the property is the density of a liquid?density of a liquid? Physical or Chemical Physical or Chemical

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Answer:

•Physical

4. While conducting an 4. While conducting an investigation using investigation using chemicals, what should be chemicals, what should be avoided when observing avoided when observing odor?odor?

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Answer:

• Taking a big whiff of Taking a big whiff of substance should be substance should be wafted towards scientistwafted towards scientist

5. A student conducts an investigation 5. A student conducts an investigation to the chemical reaction of an Alka-to the chemical reaction of an Alka-Seltzer tablet in water. What evidence Seltzer tablet in water. What evidence supports this type of reaction?supports this type of reaction?

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Answer:

•Bubbles Formed

6. A student conducts an investigation using a Ziploc bag and some chemicals. Two scoops of calcium carbonate, one scoop of baking soda, and 10ml of water are combined in the Ziploc bag. After 30 seconds, the student observe is the bag increasing in size and feels an increase in temperature.

6. What two pieces of 6. What two pieces of evidence supports a evidence supports a chemical change has taken chemical change has taken place?place?

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Answer:

• Increase in size

• Increase in temperature

7. Give an example of a 7. Give an example of a chemical change using chemical change using an apple as the an apple as the substance.substance.

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Answer:

•Rot

•Decompose

8. Give an example of a 8. Give an example of a physical property using a physical property using a shoe as the substance.shoe as the substance.

Answer:

• Color

• Size

• Density

• Texture

9. A student combines 3 grams of 9. A student combines 3 grams of baking soda with 20ml of vinegar in a baking soda with 20ml of vinegar in a 100ml beaker. The student observes 100ml beaker. The student observes bubbles rising to the surface and bubbles rising to the surface and bursting.bursting.

• What evidence supports a What evidence supports a chemical change has taken chemical change has taken place? place?

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Answer:

•Bubbles

•Odor

10. Which of the three types of 10. Which of the three types of elements would have the elements would have the characteristics of being shiny, characteristics of being shiny, ductile, and conducting heat ductile, and conducting heat well?well?

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Answer:

• Metals

11. What type of change can be observed in the ice cubes?

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Answer:

• Physical

12. Physical changes 12. Physical changes occurring during the water occurring during the water cycle. What is the process cycle. What is the process when water changes in state when water changes in state from a gas to a liquid?from a gas to a liquid?

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Answer:

•Condensation

13. The displacement 13. The displacement method was used to method was used to measure the volume of a measure the volume of a rock. What is the volume rock. What is the volume of the rock?of the rock?See Handout for diagramSee Handout for diagram

Answer:

• 25ml

Scientists use a graduated cylinder

to measure the volume of

something.

Remember volume is the amount of space an object takes up.

Because the liquid is curved, to read the volume correctly

you must look at the meniscus (the

bottom of the curve).

What is the volume of liquid in each container?

Use a graduated cylinder to measure the volume of an irregular shaped solid

•Read the beginning volume

•Drop the object in on an angle.

•Subtract the beginning volume from the new water level.

•What is the volume of the object?

To find the Volume of Solid:

Use the formula

Length x Width X Height

It doesn't matter what you consider your

length, width, or height

as long as you

DON’T MEASURE THE SAME SIDE

TWICE

Metals on the Periodic Table of Elements might have this property. What is it?

HOT WATER

COLD WATER

• Element Molecule Compound SaltElement Molecule Compound Salt

• Compound Cl2 O3 MoleculeCompound Cl2 O3 Molecule

Name properties of the elements highlighted in yellow

Name some properties of mostof the elements highlighted in

blue

Name properties of most of theelements highlighted in orange

Name properties of most of theelements highlighted in pink

• Element

• Molecule

• Compound

• Mixtures

• Solution

Match the words to the correct symbol(s)symbol(s) which would represent a correct model of them

• Common compounds and their formulas

• Hydrochloric acid HCl

• Salt NaCl

• Water H2O

• Sugar C12H22O11

• Carbon dioxide CO2

What are the elements in each? How many total atoms are in each?How many elements are in each?

• Boiling point

• Radioactive

• Density

• Non-reactive100 oC

• Look at the chemical reactions.• What do they tell you about the chemical properties of a

compound?

OXYGEN

Na + Cl NaClSilver reactive metal poisonous green gas nutrient we need to live (salt)

C + O CO2

Black brittle solid clear odorless gas dense gas we expel as waste