Give the number of significant figures in this number: 2.115

a. 4

b. 0

Which element below must be stored in oil because of its reactivity? A: Florine B: Chlorine C: Sodium D: Gold

Which molecule contains the smallest number of hydrogen atoms? A) N2H4. B) Al (OH) 3. C) (NH4) 2SO4. D) NH4NO3.

If a substance has a pH of 7, that substance is

Describe the sequence of adding ingredients to make the recipe for condensed tomato soup. To mix the ingredients, you have an industrial-sized vat with a capacity of 800 L.

Louie drinks a bottle of a water even though he is not thirsty. As a result, what will the body do to maintain homeostasis?

2NO + O2 → 2NO2 What type of chemical reaction is shown above? a combustion reaction b double displacement C synthesis d decomposition e single displacement

Why did Bromophenal solutions change from yellow to blue (what chemical reaction happended) ?

How many milliliters of calcium, with a density of 1.55 g/mL, are needed to produce 85.8 grams of calcium fluoride in the single replacement reaction below? Show all steps of your calculation as well as the final answer.

If object A is placed on the pH scale at pH = 3 and object B is placed at pH = 8, which of the following must not be true? A. Object B has a higher hydroxide ion concentration than object A. B. Object B is closer to a neutral pH than object A. C.

Laboratory safety is not an important concern for scientists. True or false