An atom has 5 protons and 7 neutrons. What is its mass number?

Calculate the heat change in calories for melting 65 g of ice at 0 ∘c.

Calculate the equilibrium constant for the decomposition of water 2h2o (l)  2h2 (g) + o2 (g) at 25°c, given that  g°f (h2o (l)) = - 237.2 kj/mol.

Which balanced equation represents a redox reaction? a. AgNO3 (aq) + NaCl (aq) →AgCl (s) + NaNO3 (aq) b. H2CO3 (aq) →H2O () + CO2 (g) c. NaOH (aq) + HCl (aq) →NaCl (aq) + H2O () d.

Boron fluoride obeys the octet rule. True or false

Explain how mass and energy are conserved when water evaporates.

The total number of valence electrons in the phosphate ion is

The reaction below has an equilibrium constant kp=2.2*106 at 298 k. 2cof2 (g) ⇌co2 (g) + cf4 (g) calculate kp for the reaction below. cof2 (g) ⇌12co2 (g) + 12cf4 (g)

The electrical conductivities of the following 0.100 M solutions were measured in an apparatus that contained a light bulb as the indicator of conductivity. Rank the solutions in order of decreasing intensity (brightest to dimmest) of the light bulb.

What is the name of a list of elements arranged according to the ease with which they undergo certain chemical reactions?

Why is it harder for the earth to recover from some natural disasters now? A) Human influence may compound the damage. B) The natural disasters have gotten worse. C) This statement is not true.