Atoms, Ions, and Chemical Reactions Review

Flashcards summarizing key concepts and questions from the lecture on atoms, ions, chemical reactions, and stoichiometry.

What is the electron, proton, and neutron composition of strontium-90?

38 electrons, 38 protons, 52 neutrons.

What is the atomic mass of element X given 20.0% 12X and 80.0% 13X?

The atomic mass is nearest to 12.8.

Which ion contains twenty-six electrons?

Fe2+.

What atomic number and mass number remain after an element with atomic number 84 and mass number 199 emits an alpha particle?

Atomic number 82 and mass number 195.

What is the most likely formula for the combination of gallium and selenium?

GaSe.

What is the formula for francium selenite?

Fr2Se2O3.

What is the formula for tetraphosphorus hexoxide?

P4O6.

What is the best name for Cr(OH)3?

Chromium (III) Hydroxide.

How many silicon atoms are in a silicon chip weighing 2.3 x 10^-4 g?

4.9 x 10^18.

How much mass of carbon is present in 1.4 x 10^20 molecules of sucrose?

2.8 x 10^-3 g.

What is the empirical formula of glyoxal consisting of 41.4% C, 3.5% H, and 55.1% O by mass?

CH2O.

What is the coefficient ratio of ClO2 to ClO3 – when balancing the equation ClO2 + OH– → ClO2 – + ClO3 – + H2O?

1:1.

How much SbF3 is needed to produce 1.00g of CCl2F2?

0.986 g.

When 3.00g C3H8O are combined with 7.38 g O2, which reagent remains?

0.006 mol O2.

What is the molarity of a solution made by dissolving 8.56 g of sodium acetate in 750 mL?

0.139 M.

What is the correct procedure for preparing 250 mL of 0.10 M NaCl solution?

Dissolve 5.84 g of NaCl in 50 mL H20 and dilute to 250 mL.

What volume of 12 M HCl is needed to prepare 500 mL of 0.60 M HCl?

25 mL.

What volume of 0.100 M SO3 2- is needed to titrate 24.0 mL of 0.200 M Fe3+?

48.0 mL.

Which combination of dilute reagents will not produce a precipitate?

NaOH + HClO4.

What is the correct net ionic equation for the reaction between Ba(OH)2 and Na2SO4?

Ba2+ + SO4 2- = BaSO4.

What is the correct net ionic equation for the reaction between H2SO4 and NaOH?

H+ + OH- = H2O.

What is the molar mass of an ideal gas with a 0.622 g sample occupying 300 mL at 35 °C?

50.5 g/mol.

What is the volume of a 500 mL gas sample collected over water at 740 mm Hg at STP?

500 x ((740-24)/760) x 273/298.

What is the final pressure when a gas is heated from -20.0°C to 57.0°C and the volume is increased from 2.00 L to 4.50 L with an initial pressure of 0.140 atm?

0.242 atm.