1) 4.20 x10^6 ml + 12.3 x 10^2 L= My answer is 4.21 x 10^9
2) Change 17.7 L to cubic meters? My answer 1.77 x 10^3
3) Draw an electron dot diagram for K3PO3
My answer K
O P O
O
I couldn't do the dots but there should be 26 dots right?
4) A 35.0 g sample of a carbon-oxygen compound is 72.7% oxygen, 15.0 % hydrogen, and the rest is carbon. How many grams of carbon are there in 12.2 g sample of the compound?
My answer 12.2g x .727= 8.86 g
5) write in scientific notation show the correct # of sig figs?
602,000,000,000,000,000,000,000
My answer 6.02 x 10^23 or x10^21
any help would be greatly appreciated. I just want to make sure I am getting my answers right
1 and 2 are incorrect.
3 I can't draw on the boards.
4 is incorrect. You calculated oxygen but the problem asked for carbon.
5. 5 is correct if you use x 10^23 (not x 10^21).
DrBob222 do you think you can help me figure these out please. On #4 would I do 12.2g x 35.0g= ??
No.
12.2 g x decimal equivalent of percent C.
1) To correctly add the given values in scientific notation, we need to make sure the exponents are the same. In this case, we have 4.20 x 10^6 ml and 12.3 x 10^2 L.
First, convert 12.3 L to milliliters by multiplying it by 1000: 12.3 L = 12.3 x 1000 = 12,300 ml.
Now, both values are in milliliters, so we can add them: 4.20 x 10^6 ml + 12,300 ml = 4.20 x 10^6 + 12,300 ml.
Next, write the sum in scientific notation by moving the decimal point to the appropriate position to obtain a number between 1 and 10: 4.20 x 10^6 + 0.00123 x 10^6 ml.
Now add the numbers: (4.20 + 0.00123) x 10^6 ml = 4.20123 x 10^6 ml.
So, the correct answer is 4.20123 x 10^6 ml.
2) To convert 17.7 L to cubic meters, remember that there are 1000 L in one cubic meter.
Divide 17.7 L by 1000 to convert it to cubic meters: 17.7 L / 1000 = 0.0177 cubic meters.
Now, write the result in scientific notation: 0.0177 = 1.77 x 10^-2 cubic meters.
So, the correct answer is 1.77 x 10^-2 cubic meters.
3) To draw the electron dot diagram for K3PO3, we need to know the number of valence electrons for each element.
K (Potassium) has 1 valence electron.
O (Oxygen) has 6 valence electrons.
P (Phosphorus) has 5 valence electrons.
Since there are three K atoms, we have a total of 3 valence electrons for potassium. For P and O, we have 5 + 6 + 6 = 17 valence electrons.
Distribute the valence electrons as dots around the atomic symbols, starting with the least electronegative atom (K) and then moving to the more electronegative (O and P).
The electron dot diagram for K3PO3 should look like this:
K
O P O
O
So, your answer is correct.
4) To find the grams of carbon in a 12.2 g sample of the compound, we first need to determine the percentage of carbon in the compound.
Given that the compound is 72.7% oxygen, 15.0% hydrogen, and the rest is carbon, we can subtract these percentages from 100% to find the percentage of carbon: 100% - 72.7% - 15.0% = 12.3% carbon.
Now, calculate the grams of carbon in a 12.2 g sample using the percentage of carbon: 12.2 g x (12.3/100) = 1.5026 g.
So, the correct answer is 1.5026 g of carbon.
5) To write the number 602,000,000,000,000,000,000,000 in scientific notation, count the number of digits and move the decimal point to the appropriate position to obtain a number between 1 and 10.
In this case, we have 24 digits. Move the decimal point to the left 24 places, and the result is 6.02.
Now, indicate the power of 10 by using 10 raised to the power of the number of decimal places you moved the decimal point: 6.02 x 10^24.
So, the correct answer is 6.02 x 10^24, indicating the correct number of significant figures.