Chem

0.0521 m Remember the slide with prefixes

5.21 cm is the same length as how many m?

424

A calculator answer of 423.6059 must be rounded off to three significant figures. What answer would you report?

First step: 0.125g/1 X 1000mg/1g (cancel out grams) Second step: 0.125g/1 X 1000mg/1g X 5.0mL/250mg (cancel out the mg to be left with the conversion factor you need mL) Last step: Multiply top then divide by bottom. The answer should be 2.5mL

A doctors order is 0.125 g of ampicillin. The liquid suspended on hand contains 250 mg/5.0 mL. How many milliliters of the suspension are required?

Temperature

A value of 25°C is a measurement of __________.

Length

A value of 345 mm is a measure of _____________.

step 1. place given value on top. with one on bottom. step 2. recognize that the conversion for kg is given and know that 1 kg = 10³g, multiply by this conversion factor with 1kg on top and 10³g on bottom so that you can cancel the grams. then multiply it by the other conversion factors keeping in mind that you are trying to cancel terms until you get the needed one being oz. Step 3. Multiply the top numbers and divide them by the bottom numbers. Answer: 1.6 oz (remember the table we drew in class)

According to the United States FDA, the recommended daily requirement of protein is 45g. This is ______ oz. of protein (1 lb= 16 Oz , 1kg = 2.20lb)

Familiarize

Be familiar with these prefixes

C. Element

Helium is a(n) _________. A. compound B. heterogeneous mixture C. element D. homogeneous mixture E. electron

First step: 30.4lb/1 X 454g/1lb (cancel out the lb) Second step: 30.4lb /1 X 454g/1lb X 1kg/1000g (cancel out the grams to be left with the conversion factor you need kg) Last step: Multiply top then divide by bottom. The answer should be 13.8kg

How many kilograms are in 30.4 lb? (1 lb =454g )

13g Remember when adding or subtracting 1) Count the number of significant figures in the decimal portion of each number in the problem. (The digits to the left of the decimal place are not used to determine the number of decimal places in the final answer.) 2) Add or subtract in the normal fashion. 3) Round the answer to the LEAST number of places in the decimal portion of any number in the problem.

The correct answer for the addition of 7.5g + 2.26g + 1.311g + 2g is ________.

13 g. REMEMBER THE SIGFIG RULE FOR ADDING AND SUBTRACTING

The correct answer for the addition of 7.5g + 2.26g + 1.311g + 2g is ____________.

milliliter

The cubic centimeter (cm³ or cc) has the same volume as a __________.

A.

Water (H₂O) is an example of: A. chemical B. Solid C. Wave D. Element E. Electric charge

109.30 For addition and subtraction, look at the decimal portion (i.e., to the right of the decimal point) of the numbers ONLY. Here is what to do: 1) Count the number of significant figures in the decimal portion of each number in the problem. (The digits to the left of the decimal place are not used to determine the number of decimal places in the final answer.) 2) Add or subtract in the normal fashion. 3) Round the answer to the LEAST number of places in the decimal portion of any number in the problem.

What is the answer, with the correct number of decimal places for this problem? 4.392g + 102.40g + 2.51g =

*0.22 mL* (When putting the problem in the calculator be sure to place the denominator in parentheses.)

What is the correct answer for the calculation of a volume (in ml) with measured numbers 28.58 / 16 x 8.02 (all under division sign)

C. 0.510

Which of the following has 3 significant figures? A. 0.005m B. 510m C. 0.510m D. 0.051m E. 5100m

A. Liter

Which of the following is a basic unit of volume in the metric system? A. Liter B. Kilogram C. Meter D. Centimeter E. Gram

A. noodle soup

Which of the following is a heterogenous mixture? A. noodle soup B. Water C. Sugar D. Tea E. Carbon

B. Solid dry ice changing to gas.

Which of the following is a physical change? A. baking a cake B. solid dry ice changing to a gas C. fermenting grapes to produce wine D. digesting a meal E. a tomato ripening

E.

Which of the following is a property of a solid? A. It takes the shape of the container. B. It fills the volume of the container. C. the particles move at a rapid rate. D. the interactions between its particles are very weak E. the particles have fixed positions and are very close together.

B. The following rule applies for multiplication and division: The LEAST number of significant figures in any number of the problem determines the number of significant figures in the answer. The number being divided are not included

Which of these conversions have the correct number of significant figures in the answer? A. 12.0 ft x 12in./1ft x 2.54cm/1in. =370 B. 24.95 min x 1hr./60min. = 0.4158 C. 24.0 kg x 1lb./2.20kg. = 11lb

D. Burning gasoline in a lawnmower

Which of these would NOT be a physical change? A. Freezing water to make ice cubes B. Tearing a piece of aluminum foil C. Boiling water for soup D. Burning gasoline in a lawnmower E. Melting gold to make jewelry.

5.4 x 10⁵

Write 540 000 in scientific notation.

Observation

You notice that there is more traffic between 8 and 9 in the morning. This would be a(n) ______________.

1 gram (micro = 10⁻⁶)

how many grams are in 1000 000 micrograms?

cancel out to be left with wanted factor (ft) and know that 1 inch = 2.54cm.

understand why this is the answer.