AP CHEMISTRY EXAM QUESTIONS 4

AP CHEMISTRY EXAM QUESTIONS 4

• The accepted value for a quantity is 5.67 g. If the measured value is 5.89 g, what is the

percent error?: 3.88%

• What is the sum of these values to the appropriate number of significant digits?

17.358 + 3.502 + 20.14 = ...: 41.00

• What is the product of these numbers to the appropriate number of signif- icant digits

56.2 x 9.2057 = ...: 517

4. How many significant digits are in the value 530,405,000: 6

5. How many significant digits are in the value 0.0050340: 5

6. What is the state of matter that has a definite shape and definite volume: -

solid

• what is the state of matter that has an indefinite shape and definite vol- ume?: liquid
• what is the state of matter that has an indefinite shape and indefinite volume?: gas

9. Example of an extensive physical property?: length

10. Example of an intensive physical property?: color

• Extensive Physical Property: A physical property that depends on how much of the

mixture there is. (Cannot be used to determine identity)

• Intensive Physical Property: A physical property that does not depend on how much of the

mixture there is, it depends on the identity. (Can be used to identify.)

13. Which is the state change in which a solid becomes a liquid?: Melting

14. What is the state in which a gas becomes a liquid?: Condensation

• Separation technique that relies on the different boiling points of the parts of the mixture?:

Distillation

• A 25.0 gram sample of magnesium oxide contains 10.8 grams of magne- sium. What is the

percent of oxygen by mass in this compound?: 56.8%

• What scientist described a positively charged core (nucleus) in the middle of a lot of empty

space: Rutherford

• What scientist described an atom made of a solid positively charged substance with

electrons dispersed through it?: Thomson

• Which scientist developed the plum pudding model/ model that's a circle with a lot of

smaller circles and particles inside of it: Thomson 1 / 2

• What scientist developed the model that has the nucleus and stuff inside the model:

Rutherford

21. Who described the existence of the neutron?: Chadwick

22. What has a charge of +1: proton

23. What has a mass of 1 amu: proton and neutron

• What makes two atoms isotopes of one another?: Same number of protons and electrons,

different number of neutrons

• What is the smallest part of an element that retains all the properties of the element?: Atom

26. How many neutrons are in an atom of chlorine?: 18

27. How many electrons are in a neutral atom of sodium?: 11

28. What is the number of protons in Fe: 26

• Which is the part of the experiment that serves as the point of comparison for the

results?: Control

30. Example of a qualitative measurement?: Color

31. Example of a quantitative measurement?: Temperature

• "A student conducts an experiment to determine the effect of adding salt on the boiling

temperature of water"

What is the independent variable?: Amount of salt added

• "A student conducts an experiment to determine the effect of adding salt on the boiling

temperature of water"

What is the dependent variable?: Boiling temperature

• "A student conducts an experiment to determine the effect of adding salt on the boiling

temperature of water"

What value should remain constant?: Volume of the water

• "A student conducts an experiment to determine the effect of adding salt on the boiling

temperature of water"

What is the control?: Sample one, 0 g of salt added

• "A student conducts an experiment to determine the effect of adding salt on the boiling

temperature of water" Reasonable hypothesis?: If salt is added to water, the water will boil at a higher temperature

• Which of the following is an observation that is evidence of a chemical change?
• the copper was teal
• the copper dissolved into water
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