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An unknown element contains 17 protons, 18 electrons, and has a mass number of 35.  Answer the following questions (10 points):   a. What is the atomic number of this element?   b. What is the name and symbol of this element?   c. How many neutrons does it contain?   d. Is this an ion?  If so, is it a cation or an anion?   e. Write the symbolic (isotopic) notation for this element.  

The density of iron is 7.87 g/mL.  Some iron was placed into a graduated cylinder containing 25.0 mL of water.  The water level rose to 37.9 mL.  Determine the mass of zinc knowing that the equation for density is d = m/V.  Please include units and the correct number of significant figures in your answer (7 points).

An acid-base neutralization reaction always involves the production of

The limiting reactant is

What are the conditions for Standard Temperature and Pressure (STP)?

A substance that has no definite volume is

One mole of sodium atom contains

What is the correct formula for iron (II) oxide?

Buffers are important to biological organisms because?

A radioactive nucleus Pb-208 undergoes an alpha decay. (a) write the complete nuclear reaction (b) if 420g of Pb-208 is initially present, how much will be left after 3 half-lives? (c) what is the mass percentage remaining after the 3 half-lives? Show work for full credit.