Chemistry Quiz

Calculate the volume of gold in a sample with a mass of 3.0 grams. ____________Express your answer to the correct number of SIG FIGS.

Identify the type of radiation by the property:

• alpha

• Negatively charged

• beta

• 2 protons and 2 neutrons

• alpha

• Increases atomic # of an isotope during decay

• beta

• has no mass or charge

• gamma

• can be blocked by paper

Using dimensional analysis, convert 65.0 years to seconds. Express your answer to the correct number of SIG FIGS. 1 year=365.2425 days

Given the work of Dalton, choose the postulates of Dalton’s Atomic Theory that have since been proven to be incorrect. For the postulate(s) you chose, describe a piece of evidence in one word that now we know proves these postulates to be incorrect.

Given the work of Dalton, choose the postulates of Dalton’s Atomic Theory below that have since been proven to be incorrect.

• Matter is composed of extremely small particles called atoms.

• Atoms of specific element are different from atoms of other elements.

• All atoms of a specific element are identical.

• In a chemical reaction, atoms are separated, combined, or rearranged.

What is the average atomic weight for lithium if it has two isotopes? The percent abundance for Li-7 is 92.5%. The percent abundance for Li-6 is 7.5%. Round to 2 decimal places.

Copper has two isotopes, Cu-63 and Cu-65. Copper's atomic mass is 63.55 amu. What is the percent abundance of each isotope for copper? Cu-63______ Round to 1 decimal place.

How many days does it take for 16g of Palladium – 103 to decay to 1.0g? The half – life of Palladium – 103 is 17 days. The answer is ________ round answer to 1 decimal place and include units in the answer.

N_t=N_o(0.5)^t/t_1/2 

In 5.49 sec, 1.20g of Argon – 35 decays to leave only 0.15g. What is the half – life of Argon – 35? The 1/2 life is ________ Round answer to 3 significant figures and include units in the answer.

N_t=N_o(0.5)^t/t_1/2 

A solid at room temperature (25°C) and normal pressure is placed in front of you. The person showing you the solid tells you it is glucose. Describe why this could or could not be true by providing evidence from the Reference Tables.