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The ________ handpiece runs at a higher torque and should never be used to cut teeth or bone. 

How many grams are in a milligram?[red1] Give answer in scientific notation.   How many centimeters are in a kilometer? [red2] Give answer as a whole number.

Assign an oxidation number to each element in the compound: Ca3(PO4)2. Don’t forget the + or – signs. Ca     [red15] P       [red16] O       [red17]  

There are 453.6 grams in 1 pound. How many kilograms are in 315 pounds? Give answer as a whole number. [red3] kilograms  

A product weighing 14.37 g was isolated from a reaction. The amount of product possible according to the calculation was 20.55 g. what was the percentage yield? Give the answer to 1 decimal place. [red30] %

Reactions can be characterized as combination, decomposition, single-displacement, or double-displacement. Categorize the following reactions. 2H2 + O2 –> 2H2O   [red23]   2KOH + H2SO4 –>K2SO4 + 2H2O   [red25]   Fe +  2H2O  –> Fe(OH)2 + H2   [red24]   CaCO3 –> CaO  + CO2      [red26]                  

Sodium combines with chlorine to form sodium chloride. Write a balanced equation for the reaction.

An irregularly shaped object weighs 68 grams. A researcher wants to know its density so she takes a graduated cylinder and fills it to 50 ml. When the object is placed in the cylinder the water volume increases to 88 ml. What is the density of the object. Give the answer to 1 decimal place. [red38] g/ml

A sample of 400 g of methane (CH4) is mixed with 600 g of chlorine (Cl2). Determine which is the limiting reactant according to the following equation.  CH4  +  4Cl2  –>  CCl4 + 4HCl Limiting reactant:    Spell out the answer. [red28]   What is the maximum mass of CCl4 that can be formed? Give the answer as a whole number. [red29] grams

Give the formula for the following compounds: Magnesium phosphate  [red10] Carbon Monoxide [red11]