Counting atoms and balancing equations

Here are the directions:

1. Identify the elements on both sides of the equation.

2. Count the atoms of each element on both sides of the equation.

3. Use coefficients when needed to balance the

equation.

Example:

Ca + O2 --> CaO

Ca - 1 Ca - 1

O - 2 O - 1

Quiz:

1. N2 + H2 -->NH2

2. K + Cl2 --> KCl

3. K + Br2 -->KBr

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.

Describe the process that was used in this lab to create magnesium oxide, specifically identifying the type of chemical reaction. explain why the product had a higher mass than the reactant, and how this relates to conservation of matter.

How will the ice water mix with the salty water? write your hypothesis below. solution hypothesis describing mixing hypothesis describing temperature (will the top be warmer, cooler, or the same as the bottom? ) solution 1 freshwater solution 2 salty water solution 3 saturated water?