Express in scientific notation. Choose the answer with the proper number of significant figures.

(3 x 10^4) (4 x 10^23) = ___

A. 12^27

B. 12 x 10^27

C. 10 x 10^27

D. 1 x 10^28

I thought it was B but that's incorrect

What concentration of the lead ion, pb2+, must be exceeded to precipitate pbf2 from a solution that is 1.00*10-2 m in the fluoride ion, f-? ksp for lead (ii) fluoride is 3.3*10-8?

if 5.00g of nitrogen gas and 15.0g of hydrogen is added to an evacuated 7.50l steel container and the steel container is sealed at room temparature of 25.5C. what is the initial temperature of each gas

When the axon terminal of a modulatory neuron (cell M) terminates close to the axon terminal of a presynaptic cell (cell P) and decrease the amount of neurotransmitter released by cell P. the resulting type of modulation is called

What are the three factors that speed up solvation also called mixing and dissolving?

Match the correct piece of glassware to its function in an acid-base titration: Erlenmeyer flask volumetric pipet buret

Which of the following would NOT be a conversion factor for mole to mole calculations for the following reaction: 2Al 3Cl2 - -> 2AlCl3?

A negative ion has more A. protons than electrons B. electrons than protons C. neutrons than protons

A team of researchers is investigating a new carbon-rich molecule important to life. They find evidence for the presence of a carbon-carbon double bond in the molecule. This observation means that the new molecule likely exists as _.

Read the list of elements given below. He, Ne, Ar, Kr Which of the following about the elements is true? All of them are unreactive gases. All of them are reactive metalloids. He and Ne are unreactive gases and Ar and Kr reactive metalloids.

Blank is the energy required for a chemical reaction to take place, and blank is the energy associated with every substance.