Author: Anonymous

Record the length of the object to the correct number of significant digits.

Which response includes all of the following that involve PHYSICAL changes, and none that involve chemical changes? a. rusting of an iron nail b. melting of gold c. digestion of food d. combustion (burning) of coal e. condensation of steam    

How many protons, neutrons and electrons are there in an atom that has an atomic number of 13 and a mass number of 25? [protons], [neutrons], [electrons] What is the symbol for the element? [symbol]

The following statements describe some physical and chemical properties of sucrose (table sugar). Which response includes all that describe CHEMICAL properties, and none that describe physical properties?   a. it is a colorless solid b. it produces a black substance and gives off vapors when mixed with sulfuric acid c. it ignites and burns with a yellow flame when heated strongly d. its density is 1.6 g/mL e. it is usually in the form of small crystals although it can also occur as a powder  

Which response lists all the substances below that are mixtures and not any pure substances? a. oxygen b. wine c. baking soda (NaHCO3) d. soil e. Cu

Classify the following as a physical or chemical change:  sweetening coffee with sugar

If necessary, use the Periodic Table below to answer the questions that follow. 

Use whichever of the following equations necessary to convert 383 K to Fahrenheit. (Use only these equations – decimal answers will not be accepted) °C = 5/9 (°F – 32) °F = 9/5 (°C) + 32 °C = K – 273  

The base unit for length in the metric system is the ____.

Which of the following correctly classifies the substance, CO2?