A chemist needs to know the mass of a sample of MgCl, to 2 significant digits. He puts the sample on a digital scale. This is what the scale shows: 0 90.30 6 g If this measurement is precise enough for the chemist, round it to 2 significant digits.

A student is given the following question:"What is the mass of a gold bar that is 7.379 × 10–4 m3 in volume?  The density of gold is 19.3 g/cm3."The student obtains the answer through the following calculation: For the above calculation, how many significant figures should you report the answer to?

V A brick has a mass of 4.0 kg and the Earth has a mass of 6.0 × 1027 g. Use this information to answer the questions below. Be sure your answers have the correct number of significant digits. What is the mass of 1 mole of bricks? Round your answer to 2 significant digits. How many moles of bricks have a mass equal to the mass of the Earth? Round your answer to 2 significant digits. 0 g x10 X S

The mass of a sample is 550 kilograms. Expresses that mass in milligrams? Express your answer in scientific notation rounded to three significant figures.

You weigh a graduated cylinder to be 58.248 grams when it is empty. You then add some unknown liquid and determine the volume of liquid to be 11.31 mL based on the marking on the graduated cylinder. You then weigh it again to find a total mass of 68.466 grams. What is the density of the unknown substance, based on these measurements? Give you answer in decimal format.

Multiply or divide the following measurements. Be sure each answer you enter contains the correct number of significant digits. 2.09 cm X 4.125 cm = 0.934 mol L X 1.65 L = 227.41 m 0.50 s = cm 2 mol m S x10 X

To reduce dangerous swelling in the brain, physicians sometimes administer intravenous hypertonic saline, a 5.0% (w/v) solution of salt NaCl in water. Calculate the mass of NaCl in 175. mL of this solution. Be sure your answer has a unit symbol and is rounded to the correct number of significant digits.

The dimensions of a rectangular object were obtained as shown below. Use the data to determine the area of the rectangle. Make sure your final answer is reported to the correct number of significant figures: Width 3.56 cm 1sam Length 5.425 cm

Calculate the mass of gold (III) chloride (Au₂Cl) that contains a billion (1.0 × 10³) gold atoms. Be sure your answer has a unit symbol if necessary, and round it to 2 significant digits. 00 x10 X 3

An iceberg has a volume of 8365 ft^3 What is the mass in kilograms of the iceberg? The density of ice in the iceberg is 0.92 g/cm^3. Express your answer using two significant figures.