when i calculate the density from my measurement,mass=154.4, volume=175.00,and got 0.8823 g/cmexp3 as the answer,so do i have to express the answer in scientific notation or round off it?

No, you do not need to express the answer in scientific notation unless the problem asks for it. Your question about rounding confuses me a little. You have 4 significant figures (sf) in 154.4 and 5 sf in 175.00; therefore, you are allowed 4 significant figures in the answer. I found 154.4/175.00 = 0.8822857. Rounded to 4 sf that will be 0.8823. I hope this helps.

To calculate density, you divide the mass by the volume. In this case, the mass is given as 154.4 grams and the volume is given as 175.00 cm^3. So, dividing 154.4 grams by 175.00 cm^3 gives you a density of 0.8823 g/cm^3.

Now, whether or not you need to express the answer in scientific notation or round it off depends on the desired level of precision and the given measurement uncertainties. In this case, you have used 4 significant figures for the mass and 5 significant figures for the volume. Generally, when multiplying or dividing measurements, the result should have the same number of significant figures as the measurement with the fewest significant figures. In your case, the mass has 4 sf, so the density should be rounded to 4 sf.

The result you obtained is already rounded to 4 sf (0.8823 g/cm^3) based on the given values and the rule for significant figures. Therefore, you do not need to express it in scientific notation or round it further unless the problem specifically asks for it or if there are additional considerations regarding measurement uncertainties.