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Identify the following as an element, compound, homogeneous mixture, or heterogeneous mixture: sand (SiO2) and sugar (C6H12O6)

A sample of matter changes directly from a solid to a gas without going through the liquid phase. What is the name of this phase change?

Provide a hypothesis for ONE of the following observations: (4 points)(a)  You sneeze every time you visit your friend’s house. OR (b)  On a cold morning, the air pressure in the tires of your automobile measures 34 pounds per square inch. After several hours of high-speed driving the pressure measures 38 pounds per square inch.

Identify the following as a physical property, a chemical property, a physical change, or chemical change: Phosphine is explosive (will explode) when combined with oxygen.

Two samples of matter have been collected and observed. The following properties were collected. (2 points) Sample A: 10.0 g grey solid, malleable, reacts with nonmetals, Density=2.3 g/mLSample B: 25.0 g grey solid, malleable, reacts with nonmetals , Density= 2.3 g/mL (a)  Are the properties recorded, physical properties, chemical properties or both? _________________(b)  Are these two samples, the same type of matter or different?_______________________________

Identify the following as a metal, nonmetal or semimetal/metalloid:  A shiny, but dark solid with electrical conductivity that can be modified.

PERIODIC TABLE IS PROVIDED FOR REFERENCE TO ANSWER THE FOLLOWING QUESTIONS:

Put yourself in the role of a scientist. You have made a hypothesis and have tested your hypothesis by repeating your experiment ten times. The results of your experimentation support your hypothesis and you publish your results. What sequence of events would have to happen next for your hypothesis to be elevated to the status of a theory?

Determine whether the following statement is TRUE OR FALSE: In order for a substance to freeze energy must be released/removed.

Determine whether the following statement is TRUE OR FALSE: Solids have the strongest attractive forces between particles in a sample.