yohei72

Please help me. i tried solving and it always came out as wrong. Thanks

Part A. convert the following

1. 245 cal to kJ. Express the value in kilojoules to three significant figures.

2. 4.35×10⁶ kJ to kcal. Express the value in kilocalories to three significant figures.

3. 4.45×10³ kJ to kW⋠h. Express the value in 2 sig figs

4. 7.04×10⁴ J to Cal.

Part B

1. Find the mass in grams of 43.6 mol Xe. Express your answer using three significant figures.

2. 1.2 mol W. Express your answer using two significant figures

I am having a hard time with significant figures. Can someone please explain the rules to me. I have an overall understanding but if i have a problem where I am taking 3.52ft x 5312ft, how many sig figs should I keep. I know when multiplying or dividing you always keep the lowest number of sig figs. However my answer is 18698.2 and only three sig figs would change the answer. Can someone please help me understand!

I got the answer +1300. However, they wanted it in sig figs. Would it be 1000?