Worksheet 8.6C Acid on rocks Samia and Carlos want to investigate the effect of acids of different pHs on some rock. They have decided to put rocks into beakers of acid at pH 1, 2, 3, 4, 5 and 6. They will leave the rocks in the beakers for two days. Then they will remove the rocks and weigh them.

Which variable are Samia and Carlos changing?
2 Which variables do they need to keep the same?
3 What safety precautions do they need to take?
4 What do they need to do to the rocks before they start the investigation?
5 Construct a results table for this experiment.

Electrons are extremely important to what area of technology? a) anti-aging research b) household product development c) electronics d) drug discovery

You are making a solution of calcium chloride dissolved in water. you add solid, stir, and it dissolves. you add just a spatula tip full, stir, and the solid does not dissolve. how could you describe the solutions before and after adding the spatula tip amount

Calculate the ratio of h+ ions to oh– ions at a ph = 7. find the concentration of h+ ions to oh– ions listed in table b of your student guide. then divide the h+ concentration by the oh– concentration. record this calculated ratio in table a of your student guide. compare your approximated and calculated ratios of h+ ions to oh– ions at a ph = 7. are they the same? why or why not? record your comparison in table a. what is the concentration of h+ ions at a ph = 7? mol/l what is the concentration of oh– ions at a ph = 7? mol/l what is the ratio of h+ ions to oh– ions at a ph = 7? : 1