& Gas P was passed over heated magnesium ribbon and hydrogen gas was collected as shown in the diagram below: bys Magnesium ribbon Hydrogen gas Gak P UZ wa 4 7 Heat (0) Name gas P (1mk) (ii) Write an equation of the reaction that takes place in the combustion tube(2mks) (ii) State one precaution necessary at the end of this experiment(1mk) Ensure hydrogen burnod is pure.​

20 pts ‼️ an unmanned spacecraft travels to mars. mars has a lower strength of gravity than earth. where in the image is the spacecraft’s weight the greatest?

1.) which of the following is a molecule but not a compound? a. he b. f2 c. h2o d. ch4 2.) what is a physical combination of substances? a. a compound b. a molecule c. a mixture d. an element 3.) what is a chemical combination of substances? a. a compound b. an atom c. a mixture d. an element 4.) what is the relationship between the solute and solvent in a solution? a. they form a compound b. they form a mixture c. they form molecules d. they form chemical bonds 5.) the gases in air dissolve in water. what would be one way to reduce the amount of a gas dissolved in water? a. add more water b. reduce the air pressure c. increase the air pressure d. stir the water 6.) how would you determine the solubility of a substance? a. find how well it dissolved various substances. b. find the mass and the volume of the substance. c. find the temperature at which the substance evaporated. d. find how much i was able to dissolve in a solute. 7.) the periodic table organizes all of the kinds of a. molecules. b. compounds. c. atoms. d. ions. 8.)what distinguishes two substances combined to become a compound vs. two substances combined to become a mixture? a. whether they can be easily separated b. whether they chemically bond together c. whether they both are visible d. whether they are heterogeneous 9.) the principle components of air are: n2 78% o2 21% ar 0.95% co2 0.038% this is a solution of a. molecules and atoms. b. molecules. c. compounds and molecules. d. atoms.

Which statement explains which component is likely to be more powerful in explaining a scientific phenomenon? a) component c, because a theory is often passed on possibility and not certainty b) component d, because a hypothesis is often based on possibility not certainty c) component c, because the ability to explain several occurrences in the natural world is a characteristic of a hypothesis d) component d, because the ability to explain several occurrences in the natural world is a characteristic of a theory