120 students took a chemistry test. 22 scored a 90.55 scored an 80, 12 scored a

70, 11 scored a 60, and 20 scored a 50. Calculate the weighted average of the test

scores.

According to Reference Table F, which of these compounds is the least soluble in water? (1) K2CO3 (3) Ca3 (PO4) 2 (2) KC2H3O2 (4) Ca (NO3) 2

Explain how both nucleic acids and proteins are both polymers?

What is the energy of a photon of green light with a frequency of 5.50 x 101^4 Hz?

Fe2o3 (s) + 3co (g) →2fe (s) + 3co2 (g) in a reaction mixture containing 189 g fe2o3 and 63.0 g co, co is the limiting reactant.

Copper is used to make electrical cable because it is a) Cheap and readily available b) Hard and brittle c) Shiny and unreactive d) Soft and can be easily stretched

In the enzyme reaction above, catechol is the substrate, oxygen is a reactant, catechol oxidase is the enzyme, benzoquinone is the product, and water (H2O) is a by-product. Which of the following will decrease the rate of this reaction? a.

How do acids and bases affect the quality of freshwater sources?

How many moles of carbon dioxide can be produced when 3.05 of calcium carbonate are heated

Which organ system has the principal function of protection, water retention, thermoregulation, vitamin D synthesis, cutaneous sensation and nonverbal communication?

1. What is the name of TiSe