Study Barn

A. John Gorton

B. Frank Forde

C. Harold Holt

D. Bob Hawke

Sir John Grey (9 September 1911 – 19 May 2002) was the 19th Prime Minister of Australia.

A. 1.00 M

B. 2.00 M

C. 3.00 M

D. 4.00 M

Molarity
Step 1: find the moles of solute using the formula:
mass of solute (g) divided by formula mass of solute
Step 2: divide the moles of solute by volume of solution in liters M / V.
Or if you know the moles of solute,
Molarity = moles of solute divided by volume of solution in liters . KF has a formula mass of 39 + 19 or 58 g/mole. Since 116 grams are given, 116g / 58g/mole = 2 moles of solute.
To find the Molarity, take 2 moles of solute and divide by 1 L of solution.
2 moles / 1 L = 2.00 M solution

A. Potassium chloride.

B. Ammonium chloride.

C. Potassium chlorate.

D. Ammonium chlorate.

Only two different kinds of atoms make up a binary compound. Potassium chloride has K atoms and Cl atoms. All other choices have 3 kinds of atoms.

A. Decreased temperature and decreased concentration of reactants.

B. Decreased temperature and increased concentration of reactants.

C. Increased temperature and decreased concentration of reactants.

D. Increased temperature and increased concentration of reactants.

Rate or speed of reaction is influenced by temperature, concentration, surface area, nature of reactants, and presence of a catalyst. To speed up a reaction, increase the number of effective collisions between molecules. Temperature is a measure of the average kinetic energy, so increasing temperature speeds up a reaction. Increasing the concentration of the reactants adds more particles and this also increases the number of effective collisions.

A. 15 cal.

B. 45 cal.

C. 150 cal.

D. 450 cal.

Multiply the heat of fusion (30 J/g) times the number of grams (15 g). Heat of fusion is the amount of heat needed to change a solid to a liquid at the melting point.    
  30 J/g x 15 g = 450 J/g

A. Octane.

B. Nonane.

C. Decane.

D. Undecane.

Decane (CH3(CH2)8CH3) has ten carbon atoms. octane has eight carbon atoms, while Nonane has nine.