This is how osmium appears in the periodic table. Rounded to the nearest whole number, how many neutrons, on average, are in an atom of osmium?

76

114

190

266

Which of the following represents an ion? Ca Na^+ Mg ^4He

An atom with a single electron (i. e. a hydrogen-like atom) has an atomic number z = 3. what is the principal quantum number of the state in which the electron has the same total energy as a ground state electron has in the hydrogen atom?

A 6.0 mol sample of C3H8 (g) and a 20. mol sample of Cl2 (g) are placed in a previously evacuated vessel, where they react according to the equation above.

Which of these can be used as an inert electrode? copper platinum silver zinc

Determine whether or not baco3 will be more soluble in acidic solution than in pure water.

A sample of three mixed gases is at 632.0 mmhg. if the partial pressure of co2 is 124.3 mmhg and the partial pressure of n2 is 461.9 mmhg, what is the partial pressure of o2?

How do the products and reactants of a chemical change compare? The mass of the products is greater than the mass of the reactants because energy is taken in by the reaction.

All the following are characteristic properties of phosphorus. Which one is a chemical property? (a) When exposed to air, white phos - phorus will burn spontaneously, but red phosphorus will not. (b) Red phosphorus and white phos - phorus are solids.

What are the monomers of proteins called

What type of fermentation occurs in yeast?