Ionic vs. Covalent
In an ionic bond what typically happens to the valence electrons?
they are completely donated / received
Which types of compounds are typically electrolytes: ionic or covalent?
ionic
Nitrogen has atomic number 7. How many valence electrons?
5
For what reason might someone drink Lactaid milk?
They do not produce lactase, the enzyme that breaks lactose into glucose and galactose
True or false: if there are 4 naturally occurring isotopes of a given element, only the two most abundant are pertinent to average atomic mass.
False, all naturally occurring isotopes are pertinent
True or False: covalent bonds typically form between two non-metal atoms
True
What is the primary reason an electrolyte solution can conduct electricity?
A. It contains a high concentration of dissolved oxygen
B. It contains free moving ions that carry charge
C. The water molecules themselves become metallic
D. It contains a large number of uncharged atoms
B
Phosphorus has atomic number 15. How many valence electrons?
5
What can one expect when testing whole milk for the presence of glucose?
whole milk contains lactose, so on its own whole milk will test negative for glucose
There is more chlorine 35 than chlorine 37. Hence, the weighted average atomic mass of chlorine will be closer to 35 or closer to 37?
closer to 35
In a covalent bond, __________ electrons are ________ in order to more closely approximate a complete _________ shell of electrons.
valence, shared, valence
What is it called when two atoms share a pair of electrons unequally?
A polar covalent bond
Magnesium has atomic number 12. How many valence electrons?
2
If the hydronium ion concentration in a given solution is 1x10^-3, what is the pH?
You can convert a percentage (such as 97%) for fractional abundance into a value to plug into an equation to calculate average atomic mass by _________ that percentage by ________
dividing, 100
Which of these substances is held together by ionic bonds?
MgO, H2O, CO2, CH4
MgO
Which of the following is an example of an electrolyte?
Distilled Water, Sugar, NaCl, Acetic Acid (vinegar)
NaCl
How many total valence electrons are in the compound H2O? Of those, how many are involved in covalent bonds?
8, 4
If the hydronium ion concentration in a given solution is 1x10^-5, what is the pOH?
9
calculate pH (5), then 14-pH = pOH
If 19.9% of Boron is Boron 10, and 80.1% of Boron is Boron-11, provide an equation for calculating the weighted average atomic mass of Boron
(0.199 * 10) + (0.801 * 11)
what type of bonding is present in a molecule of Nitrogen gas?
Beryllium Oxide is a toxic and ceramic material known for electrical resistivity and thermal conductivity. Is it polar or nonpolar? Does that make it more or less likely that it could diffuse through a cell membrane?
polar, less
How many valence electrons are present in NaCl? Of those, how many are involved in a covalent bond?
8, 0 (NaCl is an ionic compound, not a covalent compound)
If the concentrations of hydroxide ion and hydronium ion are the same in a solution, what is that solution's pH?
7
The fractional abundance of Nitrogen-14 is above 99%. Therefore the weighted average atomic mass of Nitrogen will be close to
14