Which mineral has the same hardness as a fingernail?

a. Diamond

c. Fluorite

b. Topaz

d. Gypsum

Why the physicochemical study of substances has allowed humans to use the products of these chemical processes in their daily lives?. minimum 400 words

A sample of seawater contains 1.3g of calcium ions in 3,100kg of solution. what is the calcium ion concentration of this solution in units of ppm?

Which of these is not biomass energy source? A. wind B. manure C. garbage D. lumber

The half-life of carbon-14 is 5730 years. therefore, 5730 years after being cut from a tree, a piece of wood will have 50.0% of the carbon-14 that it had originally.

What type of chemical bond would form between an atom of carbon (C) and an atom of nitrogen (N). Explain specifically why this type of bond would form.

What is the oxidation number for Our in NaHCO3?

To determine if a reaction is exoteric a student should use

Which of the following are physical properties of a penny? Choose all that are correct. Select one or more:a. Slightly red in color. b. Conducts electricity very well. c. Reacts to oxygen when heated. d. Resists corrosion from most acids.

NO2 and N2O4 undergo the reaction shown. When a sealed container of NO2 reaches chemical equilibrium, which must be true? A) No N2O4 is present. B) No chemical reactions are occurring. C) The rates of the forward and reverse reactions are equal.

What differences did you notice in the different states of water