You have three molecules of sodium bicarbonate 3NaHCO3. Which statement is true?

A.) The number of oxygen atoms (O) is less than the sum of the sodium (Na), hydrogen (H), and carbon (C) atoms.
B.) The number of sodium atoms (Na) equals the number of hydrogen atoms (H).
C.) The number of oxygen atoms (O) is greater than the sum of the sodium (Na), hydrogen (H), and carbon (C) atoms.
D.) The number of carbon atoms (C) is three times greater than the number of oxygen atoms (O).

The atomic radius of sodium is 186 pm and of chlorine is 100 pm. the ionic radius for na+ is 102 pm and for cl– is 181 pm. in going from na to cl in period 3, why does the atomic radius decrease while the ionic radius increases? a. the inner electrons in the sodium cation shield its valence electrons more effectively than the inner electrons in the chloride anion do. b. the inner electrons shield the valence electrons more effectively in the chlorine atom than in the chloride anion. c. the outermost electrons in chloride experience a smaller effective nuclear charge than those in the sodium cation do. d. the outermost electrons in chloride experience a larger effective nuclear charge than those in the sodium cation do. e. monatomic ions are bigger than the atoms from which they are formed.

(1.6 × 10-19)(5.0 × 106) = c × 10d identify the missing numbers below to show the result of multiplying the numbers.

Asample of air with a volume of 2.20m3 at a pressure of 105 kpa and a temperature of 30c is cooled to 10c and the pressure is reduced to 75.0 kpa. what is the new volume? 6.9 1.34 2.56 43.0 2.88