1. Chemistry Midterm Review

2. After the discovery of the electron by Thomson, draw and name the revised model of the atom.

3. Write the form of the density equation used to solve for VOLUME
V=m/D

4. Which group of the periodic table has two valence electrons and is comprised completely of metal elements?
Alkaline Earth Metals

5. You are asked to find the volume of a box that is 2. 5 cm high, 2
You are asked to find the volume of a box that is 2.5 cm high, 2.65 cm wide, and cm long. Solve for volume.
 23 cm3

6. Write (and label) the molar mass of LiCl.
g/mol LiCl

7. The smallest unit of an element that maintains the properties of that element is a(n) _____________.
atom

8. Which of the following has a meaning similar to “accuracy?”
A. correctness
B. repeatability
C. degree of logic
D. degree of safety

9. If a rock’s mass is 17.36 g, which of the following data sets demonstrates precision?
A g, g, g
B g, 12.01g, g
C g, g, g.
D. None of the above

10. Which group of the periodic table has a full set of valence electrons?
Noble gases

11. How many significant figures are in the following measurement? 0.002510 g
Four (4)

12. A liquid measures 15 mL when placed in a graduated cylinder
A liquid measures 15 mL when placed in a graduated cylinder. What will its volume be when it is transferred to a beaker?
15 mL

13. NaCl O2 NO3-1 Au BaBr2 NaCl – compound and formula unit
Decide if the following are atoms, compounds, ions, molecules, elements, and/or formula units.
NaCl O2
NO3-1 Au
BaBr2
NaCl – compound and formula unit
O2 - element and molecule
NO3-1 – compound, ion and molecule
Au – atom and element
BaBr2 – compound and formula unit

14. Consider the element oxygen
Consider the element oxygen. List one PHYSICAL and one CHEMICAL property of oxygen, and label them as such.
PHYSICAL PROPERTIES INCLUDE: Diatomic gas at room temperature, colorless, odorless CHEMICAL PROPERTIES INCLUDE: It supports combustion, combines with metals to form oxides (such as rust)

15. Ionic compounds are always solids at room temperature
Ionic compounds are always solids at room temperature. What determines the state of matter for covalent compounds?
For covalent compounds, the state of matter is determined by the attraction between the molecules, called intermolecular forces (IMFs). These types of forces are classified as dispersion forces, dipole-dipole interactions, and hydrogen bonds

16. Draw the molecule H2S, and label the shape.
BENT

17. Draw the molecule SiH4, and label the shape.
Tetrahedral
BENT

18. You have a sample of SO2 containing 5. 01 x 1025 molecules
You have a sample of SO2 containing 5.01 x 1025 molecules. Determine the number of grams.
Molar mass is g / mol SO2
5.01 x 1025 molecules x mol x g =
6.022x 1023 molecules 1 mol
=  5330 g SO2

19. All matter is made of atoms and molecules that are
A. always fixed in position.
B. moving in the same direction.
C. always in motion.
D. moving slowly.

20. Atoms have no charge because they
A. have an equal number of charged and noncharged particles.
B. have neutrons in their nuclei.
C. have an equal number of electrons and protons.
D. have an equal number of neutrons and protons.

21. Valence electrons determine an atom’s
A. mass.
B. electric charge.
C. chemical properties.
D. period.

22. Consider a d sublevel. How many orbitals does it contain, and what is the maximum number of electrons it can hold? Draw seven (7) electrons occupying a 3d sublevel in orbital notation.
A d sublevel contains 5 orbitals and can hold a maximum of 10 electrons ↑↓ ↑↓ ↑ ↑ ↑ 3d

23. Describe the photoelectric effect and what it demonstrated about light.
Einstein’s photoelectric effect is the name given to the phenomena by which a metal will give off photons (light) when exposed to certain wavelengths of light energy. This demonstrated the way in which light can behave as a particle.

24. It is a transition metal
A substance is described as a shiny silver solid that can form multiple different cations. Categorize this element.
It is a transition metal

25. Which of the following elements is found within the “p” block of the periodic table?
A. U (92)
B. V (23)
C. K (19)
D. Cl (17)

26. What is Mendeleev is known for?
He published the first periodic table, which was based upon atomic mass and chemical properties. This was revised by Moseley to be arranged in order of increasing atomic number.

27. Write the reaction for the alpha decay of 24195Am
24195Am → 23793Np + 42He

28. Add the following numbers: 16.6 mL + 2.013 mL

29. Think about the periodic table … what information is given by the ROW and by the COLUMN? And, what are these called?
The PERIOD (or row) gives the number of energy levels in an atom of the element.
The GROUP (or column) gives the number of valence electrons (and therefore the chemical properties) of atoms of that element

30. Write correct formula for Aluminum hydroxide?
Al(OH)3

31. Write the noble gas shortcut for the electron configuration of Vanadium
V = [Ar] 4s2 3d3

32. Write the electron configuration for phosphorus.
1s2 2s2 2p6 3s2 3p3

33. In which type of bond do atoms share electrons
In which type of bond do atoms share electrons? These types of bonds will form between which type of elements?
covalent bonds – these types of bonds form between non-metals

34. Which element will have higher electronegativity?
A. I
B. F
C. Both will be equal

35. What type of bond is formed between Cesium and Fluorine
What type of bond is formed between Cesium and Fluorine? Based upon this answer, list TWO properties of this compound. Also, write its formula and name.
Ionic bond Solid, high melting and boiling point, forms crystals, likely is water soluble, conducts electricity when dissolved CsF – cesium fluoride

36. Write correct formulas and names for the following:
Ca3N2 calcium nitride
Mn3(PO4)2 manganese (II) phosphate
Ag(s) silver metal
PCl3 phosphorus trichloride
Br2(g) bromine gas
A compound formed from calcium and nitrogen ions
A compound formed from the manganese (II) ion and phosphate
Silver metal
A compound made from one phosphorus atom and three chloride atoms
Bromine gas

37. Determine the number of atoms in 6.22 g of AlCl3.
Molar mass = g/mol AlCl3
6.22 g x 1 mol AlCl3 x x 1023 particles AlCl3 x 4 atoms =
g mole particle AlCl3
x 1023  1.12 x 1023 atoms

38. The correct name and formula for the compound made from potassium and bromine would be …
KBr
Potassium bromide

39. It will have a positive two (+2) charge and be a cation
Write the charge of a particle of an element which LOST two electrons. Will this be a cation or anion?
It will have a positive two (+2) charge and be a cation

40. Consider the element sulfur
Consider the element sulfur. List its number of protons and valence electrons. List the ion TYPE and charge. Is it a metal or non-metal?
Sulfur has 16 protons and 6 valence electrons It forms a -2 cation It is a non-metal

41. Which element will have higher ionization energy
Which element will have higher ionization energy? This means that it is harder to remove electrons.
A. Fr
B. Li
C. Both will have the same ionization energy

42. Good luck on your exams!