Make the following conversions: (c) 294 °C to K

Make the following conversions: (d) 832 K to °C

Make the following conversions: (e) 721 K to °F

Make the following conversions: (f) 35 °F to K.

(a) A child has a fever of 101 °F. What is the temperature in °C?

(b) In a desert, the temperature can be as high as 45 °C, what is the temperature in °F?

(c) During winter, the temperature of the Arctic region can drop below -50 °C, what is the temperature in degree Fahrenheit and in Kelvin? (d) The sublimation temperature of dry ice is -78.5 °C. Convert this temperature to degree Fahrenheit and Kelvin. (e) Ethanol boils at 351 K. Convert this temperature to degree Fahrenheit and degree Celsius.

(a) A sample of tetrachloroethylene, a liquid used in dry cleaning that is being phased out because of its potential to cause cancer, has a mass of 40.55 g and a volume of 25.0 mL at 25 °C. What is its density at this temperature? Will tetrachloroethylene float on water? (Materials that are less dense than water will float.)

(b) Carbon dioxide (CO₂) is a gas at room temperature and pressure. However, carbon dioxide can be put under pressure to become a 'supercritical fluid' that is a much safer dry-cleaning agent than tetrachloroethylene. At a certain pressure, the density of supercritical CO₂ is 0.469 g/cm³. What is the mass of a 25.0-mL sample of supercritical CO₂ at this pressure?

(a) To identify a liquid substance, a student determined its density. Using a graduated cylinder, she measured out a 45-mL sample of the substance. She then measured the mass of the sample, finding that it weighed 38.5 g. She knew that the substance had to be either isopropyl alcohol 1density 0.785 g/mL² or toluene (density 0.866 g/mL). What are the calculated density and the probable identity of the substance?

(b) An experiment requires 45.0 g of ethylene glycol, a liquid whose density is 1.114 g/mL. Rather than weigh the sample on a balance, a chemist chooses to dispense the liquid using a graduated cylinder. What volume of the liquid should he use?

(c) Is a graduated cylinder such as that shown in Figure 1.21 likely to afford the accuracy of measurement needed?

(d) A cubic piece of metal measures 5.00 cm on each edge. If the metal is nickel, whose density is 8.90 g/cm³, what is the mass of the cube?

(a) After the label fell off a bottle containing a clear liquid believed to be benzene, a chemist measured the density of the liquid to verify its identity. A 25.0-mL portion of the liquid had a mass of 21.95 g. A chemistry handbook lists the density of benzene at 15 °C as 0.8787 g/mL. Is the calculated density in agreement with the tabulated value?

(b) An experiment requires 15.0 g of cyclohexane, whose density at 25 C is 0.7781 g>mL. What volume of cyclohexane should be used?

(c) A spherical ball of lead has a diameter of 5.0 cm. What is the mass of the sphere if lead has a density of 11.34 g>cm3? (The volume of a sphere is 14>32pr3, where r is the radius.)

Use of the British thermal unit (Btu) is common in some types of engineering work. A Btu is the amount of heat required to raise the temperature of 1 lb of water by 1°F. Calculate the number of joules in a Btu.

A watt is a measure of power (the rate of energy change) equal to 1 J/s. (a) Calculate the number of joules in a kilowatt-hour.

A watt is a measure of power (the rate of energy change) equal to 1 J/s. (b) An adult person radiates heat to the surroundings at about the same rate as a 100-watt electric incandescent light bulb. What is the total amount of energy in kcal radiated to the surroundings by an adult over a 24 h period?

Indicate which of the following are exact numbers: (a) the mass of a 3- by 5-in. index card, (b) the number of ounces in a pound, (c) the volume of a cup of Seattle's Best coffee, (d) the number of inches in a mile, (e) the number of microseconds in a week, (f) the number of pages in this book.

What is the number of significant figures in each of the following measured quantities? (b) 3ⅹ10^-6 m

What is the number of significant figures in each of the following measured quantities? (d) 2.94×10³ m²

What is the number of significant figures in each of the following measured quantities? (e) 92.03 km

Indicate the number of significant figures in each of the following measured quantities: (e) 89.2 metr ic tons

Round each of the following numbers to four significant figures and express the result in standard exponential notation: (a) 102.53070

Round each of the following numbers to four significant figures and express the result in standard exponential notation: (e) −0.0357202.

(a) The diameter of Earth at the equator is 7926.381 mi. Round this number to three significant figures and express it in standard exponential notation.