Stephen's Responses in WyzAnt Answers

You want to use the Ideal gas Law for this problem since you have all the necessary information.

PV=nRT

Solve for n

PV/RT=n

plug in your information, remembering to use 0.08206 L·atm·mol−1·K−1 for R and to convert 29C to Kelvin.

Now you get how many moles of N you have.

12.09 moles N * 14.01g/mole N = 170 g. N

The key here is to see what information you have and to use the correct units. By always paying attention to the units, you can reduce most of your errors.

Scientific Notation is done by reducing the number that you have to a number between 1 and 10. Then you have that number multiplied by the proper factor of 10 to get your original number.

 For instance,

1,030,000 to be written in scientific notation, you have to make it a number between 1 and 10. So the original number becomes:

1.03 You keep your sig figs. Notice we had to move the decimal place 6 places to the left. So we multiply our number by 10 to the 6th power and it looks like this.

1.03 * 10^6

Well, the answer is that there is no easy way to balance chemical equations. Some ways are easier than others but they all require some guesstimation. The best formula I've found to balance equations is to do the steps in the following order.

-Metals

-Non-metals

-Unchanged polyatomic ions (Nitrates, sulfates, etc.)

-then either Hydrogen or Oxygen depending on which one works better

After that, just go back through and double check. Sometimes you have to play with it a little bit. Let me give you an example to see if it helps clear things up and make them any easier.

Ca₃P₂ + H₂O --> Ca (OH)₂ + PH₃

So balance the calcium first. There's three on the left side. So we'll add a 3 to the front of of Ca(OH)₂. Remember you can only add numbers to the front of the substances, not the subscripts. So we get:

Ca₃P₂+ H₂O --> 3Ca (OH)₂ + PH₃

Now, we balance the Phosphorus. There's 2 on the left, but only one on the right. It needs to be multiplied by 2. So we put the 2 in front of PH_3.

Ca₃P₂ + H₂O --> 3Ca (OH)₂ + 2PH₃

Now the Calcium (metal) and Phosphorus (non-metal) are both balanced. Let's work on the Hydrogen. We have 2 on the left, and 12 on the right. So we need to add a 6 in front of the H₂O on the left. Doing that we get the following:

Ca₃P₂ + 6H₂O --> 3Ca (OH) ₂ + 2PH₃

Now everything is balanced except the Oxygen. We have 6 on the left and coincidentally we have 6 on the right. It balanced itself by balancing the water.

If you work them this way, it will save you from most problems. Hope this helped.

First thing you do is take get everything on the opposite side of x. To do that, start by taking the parenthesis off first. Then take the (-7) and moving it over.

x/-4 + (-7) = (-16)

x/-4 - 7 = -16

x/-4 - 7 + 7 = -16 +7  Remember, whatever you do to one side, you have to do to the other.

x/-4 = -9  Now multiply both sides by -4

x= 36 Remember, the negatives cancel out

Now plug it back into the the original equation to see if it works.