# Help with chemistry problems please!

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#### Atl21

##### Full Member
10+ Year Member

1. The law of multiple proportions is illustrated by which of the following pairs of compound? Can you explain your answer please?
A. MgCl2 and AlCl3 B. Na2O and NaOH C. CO and CO2 D. NO2 and SO2

2. The rate law for a particular reaction is Rate = K[A]^2. If for a particular run of this reaction, the concentration of B were tripled over what it hab been in the previous run but the concencentration of A remained the same, what would be the effect on the rate?

Thanks a lot

#### Knickerbocker

##### Full Member
10+ Year Member
1. The law of multiple proportions is illustrated by which of the following pairs of compound? Can you explain your answer please?
A. MgCl2 and AlCl3 B. Na2O and NaOH C. CO and CO2 D. NO2 and SO2

2. The rate law for a particular reaction is Rate = K[A]^2. If for a particular run of this reaction, the concentration of B were tripled over what it hab been in the previous run but the concencentration of A remained the same, what would be the effect on the rate?

Thanks a lot

1. When two elements form different compounds, the ratios are small, whole numbers. CO is 1:1 and CO2 is 1:2.

CO and CO2

2. Pretend that the concentrations were 1M each, pretend that K=1:

rate = [1][1]^2 = 1
Now, triple B
rate = [1][3]^2 = 9

So the reaction rate is now nine times faster.

#### Atl21

##### Full Member
10+ Year Member
thanks man, you make this so easy now