Final Review Chemistry HRA – Flashcards
Unlock all answers in this set
Unlock answersquestion
What is the molecular mass of Ni(OH)2 |
answer
a.92 b. chapter 10 c. mass of one mole d. careful with ( ) |
question
How many protons in Na |
answer
a. 11 b chapter 4 c. protons equal atomic number d. protons also equal electrons in a neutral atom e. Atomic mass- protons= neutrons |
question
Write the electronic configuration for Al |
answer
a. 1s22s22p63s23p1 b. chapter 5 c. pattern on periodic table d. s hold 2 p-6 d-10 f-14 e. know sectionson table |
question
What volume should one mole of a gas occupy at STP |
answer
a. 22.4 liters b.chapter 10 c. pv=nrt for non STP conditions d. does not matter what type of gas e; one mole of any gas occupuies the same volume under the saem conditions of temp and pressure |
question
What is pH of an acid |
answer
A. LESS than 7 b chapter 19 c. ph measures the amount of H+ d. ph= -log(H+) ph+pOH=14 |
question
What is the charge of N in the compound NF3 |
answer
a. +3 b. chapter7 c in a compound total charge is zero d positive and negative must balance e. check perodic table for most likely charge. certain group-s have specific charges |
question
Determine the density of a liquid whose mass is 50.0 grams and the volume is 25 ml |
answer
a. 2 grams/ ml b. chapter 3 c. density = m/v then d x v = mass m/d= v check units |
question
The bond angle in a water molecule is closest to? a. 180 b. 109.5 c. 105 d. 120 |
answer
a. close to 105 b chapter 8 c each shape has different bond angles d. |
question
convet 35 grams to kg |
answer
.035 kg chapter 2 dimentional anaylsis KING HENRY |
question
Balance the following reaction Al + F2 ----> AlCl3 |
answer
a. 2Al + 3F2 ----> 2AlCl3 b. Chapter 11 c. conservation of mass |
question
If 2 moles Al reacts, how many moles of AlF3 form |
answer
a. 2 moles b. Chapter 11 c. coefficentw represent ratio by number nooottttttt by mass d. mass- mass problems |
question
Which molecule is trigonal? a. H2O b, AlCl3 c. NF3 d. BrF3 1) NF3 2) H2O 3) AlCl3 4) ClF3 5) all of thes |
answer
a.AlCl3 b. chapter 8 c. trigonal molecules has 120 bond angles with 3 pair of electrons. |
question
What is the bond angle associated with the tetrahedral shape |
answer
a. 109.5 b. chapter 8 c. every shape has different bond angles d. tetrahedral has 4 pair of electrons in 3d |
question
If the hydroxide (OH) ion concentration level is .000001, then the pH is? |
answer
a.8 b. chapter 19 c. log of H= pH and log (OH)= pOH d. log .000001 = 6 = pOH e. pH + pOH =14 |
question
Determine the density of a liquid whose mass is 50.0 grams and the volume is 25 ml? |
answer
a. 2.0 g/ml b. chapter 3 c. D=m/v d. although 50.0 has 3 sig fig 25 only has 2laces of accuracy. Ans 2 places |
question
How many protons are present in a carbon atom? |
answer
a. 6 b. chapter 4 c. protons equal atomic number d. protons also equal electrons in a neutral atom e. Atomic mass- protons= neutrons |
question
What is the salt created when H2SO4 and sodium hydroxide react? |
answer
a.Na2SO4 b. Chapter 19 chapter 7 c. ion charges must equal zero d. Since Na is +1 and SO4 is -2 formula must be Na2SO4 |
question
In the compound HXO3, what is the oxidation state(charge) of element X? |
answer
a. 5 b. chapter 7 c in a compound total charge is zero d positive and negative must balance e. check perodic table for most likely charge. certain group-s have specific charges |
question
How many molecules are present in 328 grams of sodium phosphate? |
answer
a. 1.2 x10^24 molecules b. chapter 10 c. Since the molar mass is 164, 328 is equal to 2 moles of sodium phosphate. d. 2 moles represents 6.02x10^23 *2 molecules |
question
What is the volume that 35.2 g of CaCO3 will occupy if it has a density of 1.60? |
answer
a. 22.0 cm3 b. Chapter 3 c. there are 35.2 grams and 1.60 grams fit into one cubic centimeter, 35.2/1.60=22.0 d.significant figures makes it three places of accuracy |
question
How many moles are in 1.81E24 atoms of K? |
answer
a. 3 b. Chapter 10 (I think) c. divide 1.81E24 by 6.02E23 to find number of moles |
question
What is the number of significant digits in the number 20.04080? |
answer
a. 7 b. Chapter 3 c. the zero at the end is significant because it is after the decimal |
question
How many moles of oxygen atoms are in 1 moles of Ba(NO3)2? |
answer
a. 6 moles b. Chapter 10 c. count the number of molecules of oxygen in the formula (easy way) or do a percentage by mass equation (hard way) |
question
What volume would 2 moles of helium gas occupy at STP? |
answer
a.44.8 l b. chapter 10, pg. 300 c. 1 mole of gas at STp occupies a colume of 22.4 d. it's called the molar volume of the gas e. STP means standard temperature and pressure |
question
If 2 liters of a gas at 1 atm is compressed down to 1 liter, then the new pressure should be? |
answer
a. 2 atm b. Chapter 14: Gases c. Boyle's Law: PV=PV d. pressure increases when gas is compressed |
question
Which of the following atoms has the largest radii? a. Br B. Cl C. F D. I |
answer
a. I b.Chapter 6 c.To find the largest radii the size generally increases going down the table and decreases going from left to right. |
question
How many neutrons are present in Ba-140? |
answer
a. 84 b. chapter 4, pg 111 c. the neutons and protons add up to be the mass. the mass in this case is 140. the number of protons is the atomic number. so subtract 56 (the atomic number) from 140 to get 84 |
question
How many electrons are present in U+4? |
answer
a. 88 b. Chapter 7: Ions c. ions with a positive charges means that the element lost electrons |
question
How many Valence electrons does AL have? |
answer
a.Three b.Chapter 7 c. To find the number of valence electrons in an atom of an element is to look at the group number. |
question
A balloon is filled to a volume of 2.0 liter is heated from 25 C to 50 C. What is the volume of the gas at a higher temperature? |
answer
a. 2.17 liters b.chapter 14 c.Charles' Law: v1/t1=v2/t2 |
question
what is the molar mass of NH4NO3? |
answer
a.80g b.chapter 10 c. find the mass of each element and add them together |
question
What is the molecular mass for baruim hydroxide? |
answer
a. 171 b. Chapter 9/10 c. Ba is +2; OH is -1. d. Make formula and add weights |
question
How many atoms are in 2.00 mol of Na? |
answer
a.1.20 X 10^24 b.chapter 10 c. in every 1 atom there is 6.02 X 10^23 |
question
which of the following molecules is polar? a. CH4 b. CO2 c. NF3 d. BaCl2 |
answer
a. NF3 b. chapter 8 c. a molecule is polar when the electrons are shared unequally d. electronegativity is the ability of a molecule to attract electrons. |
question
How many atoms of chloride are present in 1 mole of CaCl2? |
answer
A.) 1.2 X 10^24 B.) Chapter 10 |
question
What is the molarity of NaOH created by dissolving 40 grams of NaOH into enough water to make 2 liters of a solution? |
answer
a. .5M b. Chapter 16 c. Molarity is the number of moles over 1 liter solution |
question
the electronic configuration for Al+3 is the same as what element? |
answer
a. Ne b. chapter 5 c. goal of elements are to be completly stable like Noble Gases. |
question
38.) What is the molarity of a solution with 41.6 CaCl2 in 750.0 cm^3 of water? |
answer
A.) .5M B.) Chapter 16 |
question
How much would 2 moles of carbon dioxide weigh? |
answer
a. 88g b Chapter 10 c. atomic mass x # of moles is the weight in grams |
question
What is the concentration of hydronium ion if the pH is 3.6 ? |
answer
a. 2.5 x 10^-4 M b. Chapter 19 c. [H+]= 10^-pH d. don't forget the negative sign |
question
What is the pHO for a solution containing 2.5 x 10^-4 M hydroxide ions ? |
answer
a. 3.6 b. Chapter 19 c. pHO= -log[OH-] d. dont forget the negative sign |
question
Which atom is most similar in its properties to Barium? a)Hydrogen b)Lithium c)Cesium d)Strontium |
answer
A)Strontium B)chapter 6 C)elements of the same group are similar |
question
10*C is equal to what in Kelvin. |
answer
a. 283*K b. chapter 8 c. K=C+273 |
question
What is the shape of a molecule of NBr5? |
answer
a. trigonal bipyramid b. chapter 8 c. N is +5 d. Br is -1 e. five atoms of Br off of N |
question
Consider a sealed cylinder with a moveable piston inside. As the piston moves down, the pressure inside the cylinder should a)increase b)decrease c)stays the same |
answer
A) increases B) chapter 14 C) as the piston moves down, the volume decreases but the amount of "stuff" there stays the same |
question
Which of the following contains the greatest number of atoms ? 1.) 2.5 moles of Sodium 2.) 1.5 grams of Nickel 3.) 22.4 liters of Neon at STP 4.) 3.0 grams of Sodium |
answer
a. 2.5 moles of Sodium b. chapter 10 c. find out the number of moles of each d. the greater number of moles the greater the number of atoms |
question
How many moles of gas would occupy a sealed 2.0 liter flask at a pressure of 2.0 atmospheres and a temperature of 373K |
answer
a. .131 b. PV=NRT c.R= .0821 because pressure of atm |
question
the outermost electron configuration of hafnium is ? |
answer
a. 5d2 b. chapter 5 c. memorize what group it is in d. memorize the order they go in on the peridoic table |
question
Which of the following ions is the largest? a.Na+ b. Mg+2 c. Fe+2 d. Br- |
answer
a.Br- b. Chapter 6 c. There is an extra electron added to bromine. d. look at location on the periodic table and atomic weight. |
question
How would we name the compound Fe2O3? |
answer
a. Iron(III)Oxide b. Chapter 9 c. Don't forget roman numerals |
question
How many electrons can the 4th level hold? |
answer
a. 32 b. chapter 5 c. s=2 p=6 d=10 f=14 2+6+10+14=32 |
question
How would we name the compound Fe2O3? |
answer
a. Iron(III)Oxide b. Chapter 9 c. Don't forget roman numerals |
question
How would we name the compound Fe2O3? |
answer
a. Iron(III)Oxide b. Chapter 9 c. Don't forget roman numerals |
question
The temperature at STP should be: |
answer
a. 273 K b. chapter 10 c. STP=0 degrees C d. Celcius + 273 = degrees Kelvin |
question
According to Bronsted and Lowry, acids are proton: |
answer
a. donors b. chapter 19 |
question
Which molecule is not polar? a. HBr b. H2O c. NH3 d. CCl4 |
answer
a. CCl4 b. Chapter 5 c. non polar molecules do not have any unbonded pairs of electrons. |
question
Which sublevel contains a maximum of 5 pairs of electrons? |
answer
a. d b. Chapter 5 c. pairs=2 |
question
The bonding in ethane is? (C2H6) |
answer
a. Nonpolar Covalent b. Chapter 8 c. Electronegativity |
question
What is the electron configuration for gallium? |
answer
a. 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d10, 4p1 b. Chapter 5 c. Look at columns |
question
An atom with a charge is called an? |
answer
a. Ion b. Chapter 6 c. Don't be stupid JP d. + ions have fewer electrons e. - ions have more electrons |
question
Covalent bonds are characterized by: |
answer
a. shared electrons b.chapter 8 c.covalent relates to two electrons d. in order to be covalent, they need to be shared. |
question
Oxygen has a volume of 1.429 dm3 at STP. Which of the following will result in the greatest change in volume? |
answer
a. doubling the temperature and halving the pressure b. chapter 13 c. pv=nrt (do it multiple times) |
question
What is the new volume of a gas that occupies 45.0 cm^3 at 49 C when it is cooled to -29 C if the pressure remains constant? |
answer
a. 34.1 cm^3 b. Chapter 13 c. V/t=v/t D. convert to K |
question
A molecure having 3 shared pairs of electrons and one unshared pair of electrons would have this shape: |
answer
a. irregular tetrahedral b. chapter 8 c.at least trigonal because there are 3 pairs of covalent bond d. the unshared electrons add another side making it tetrahedral e. its irregular becuase the fourth side is unshared. |
question
Which of the following gases has the greatest rate of diffusion (speed) if all are at the same temperature and pressure? |
answer
a. hydrogen b. chapter 13 c. small is the fast |
question
Which of the following bonds would be ionic? a. CH4 b. NO2 c. XeF6 d. MgCl2 |
answer
a. d, MgCl2 b. Chapter 7 c. Larger the electronegativity, the more ionic d. opposite sides of the periodic table |
question
How many electrons are in a double bond? |
answer
a. four b. Chapter 8 c.a double bond is two PAIRS of electrons. d. remember the octet rule |
question
What is the maximum number of electrons that may occupy one orbital? |
answer
a. two b. Chapter 5 c. look at Table 5.1 on pg. 131 and Table 5.3 on pg. 134 both in the textbook |
question
Which atom has a half full sub-level? 1)Ni 2)p 3)La 4)U 5)Ne |
answer
a. P b. Chapter 5.2 c. the p level has 6 sublevels and Phosphorus has three sub levels, so it's half full. |
question
If an atom loses electrons, its charge is? |
answer
a. positive b. chapter 4 c. positive atoms have more protons then electrons, so they have to give away electrons to become positive. |
question
How many atoms are present in 28 grams of silicon? |
answer
a. 6.02*10E23 b. chapter 10 c. make your triangle with moles, volume and number of atoms. divide the grams by the weight of silicon, then multiply it times 6.02*10^23 |
question
Which compound is the most polar? a. CO b. CaO c. KF d. CaI e. LiH |
answer
a. KF b. Chapter 11 c. Remember Fluorine has a very high elctronegativity! |
question
What is the concentration of Hydrodium (H+) ions in a neutral solution at 25 C? |
answer
a. 1X10E-7 b. chapter 16 c. neutral solutions have equal Hydronium and Hydroxide concentrations. |