(Mc Graw Hill)Cell Nutrition Ch. 4, 6, 7
Match the following terms used in a chemical equation with their definitions.
(l) - This reactant or product is a liquid (aq) - This reactant or product is an aqueous solution Triangle symbol - Heat needs to be added for this reaction to occur 1,2,3,... - Coefficients needed to balance an equation
Nuclear Fusion
(to join together) - combination of two small nuclei to form a larger nucleus • Large amounts of energy is released • Sun • No commercially successful plant exists in U.S.
Alpha particle (α)
(α) - 2 protons, 2 neutrons • Same as He nucleus (He2+) • Slow moving, and stopped by small barriers • Symbolized in the following ways:
Nuclear Fission
- (splitting) occurs when a heavy nuclear particle is split into smaller nuclei by a smaller nuclear particle (like a neutron) - Is self-perpetuating - Can be used to generate steam
Figure out the statement that correctly interpret the following balanced equation: 4C(s)+S8(s)->4CS2(l)
- 4 atoms of carbon react with 1 molecule of S8 to form 4 molecules of CS2 - 4 moles of carbon react with 1 mole of S8 to form 4 moles of CS2 - Carbon and S8 are reactants and CS2 is the product
Select the statements that correctly describe the effects of a nonvolatile solute on solution properties.
- A nonvolatile solute will decrease the freezing point of a solution - A nonvolatile solute will increase the boiling point of a solution.
What statements correctly describe the process of hemodialysis?
- A semipermeable membrane that can diffuse water and other waste products is used - A machine, or an "artificial kidney", is used - The dialyzing fluid is isotonic with normal blood
Which types of particles are transported in the body by blood?
- Anions - Cations - Nutrients - Nitrogenous waste - Proteins
Select all the statements that describe a colloid.
- Colloidal particles are larger in diameter than solution particles - It consist of a mixture of solute and solvent particles - Colloids scatter light, unlike liquid solutions.
In a balanced chemical equation, which of the following must be the same on both sides of the equation?
- Elements represented: in a chemical reaction equation, any elements in the reactants must also appear in the products and vice versa - Number of moles of each element
Which of the following actions are permitted in balancing a chemical equation?
- Inserting coefficients before the formulas of reactants and products - Multiplying all coefficients by a common factor
Which of the following correctly describe active transport in a cell?
- It occurs via embedded proteins in the cell membrane - Cellular energy is expended during the pumping process.
Which of the following are described in a complete balanced chemical equation?
- Physical states - Reaction arrow - Coefficients - Products - Reactants
Bases
- Taste's bitter, are slippery, are corrosive - A substance, when dissolved in water, dissociates to produce hydrogen ions - proton (H+) acceptor
Acids
- Tastes sour, dissolves some metals, cause plant dye to change color - dissociates to produce hydrogen ions - proton (H+) donor
What statements support the conclusion that a mixture of ethanol and water is a solution?
- The components do not separate upon sitting over time - The mixture is uniform throughout
Radiocarbon Dating Limitations
- The half-life of carbon-14 is 5730 years - The carbon-12 does not decay; it is the stable isotope - The ratio of carbon-12 to carbon-14 enables us to calculate the age of an artifact - This dating technique is limited to objects less than 50,000 years old (9 half-lives)
Which of the following are general trends in solubility?
- The more similar the polarities of solute and solvent, the more soluble the solute. - In general, an increase in temperature leads to an increase in solubility of solids in liquids
What are the appropriate definitions in the freezing point depression equation?
- Triangle symbol Capital "T" & subscript "t" =The extent of freezing point depression - Lowercase "k" & subscript "f" = Proportionality factor - m = solute particle concentration
Which of the following observations would be evidence that a chemical change is occurring?
- Two colorless solutions turn blue when combined - A reaction solution suddenly becomes hot - A solid precipitate forms
Beta Decay
- Upon decomposition, nitrogen-16 produces oxygen-16 and a beta particle - In beta decay, one neutron in nitrogen-16 is converted to a proton and the electron, the beta particle is released
Binding Energy
- the energy that holds the protons, neutrons, and other particles together in the nucleus - Binding energy is very large - When a nuclide decays, some energy is released because the products are more stable
Two theories that help us to understand the chemistry of acids and bases
1. Arrhenius theory 2. Bronsted-Lowry theory
Match each mixture with its correct description: - Fog -> - Chocolate Chip Cookies -> - Hot Tea ->
1. Colloid 2. Heterogenous Mixture 3. Solution
Correctly order the steps necessary to balance a chemical equation
1. Count the elements that are not balanced 2. Determine the elements that are not balanced 3. Use coefficients to balance one element at time. 4. Do a final check to make sure the equation is balanced
Match all of the variables in the equation for Henry's law with the correct identity: M=kP. - M = - k = - P =
1. Molarity 2, Henrys law constant 3. Pressure
Whats the order for writing a precipitation reaction as a net ionic equation, First to Last.
1. Write a balanced molecular equation, using solubility rules to identify any precipitates 2. Write an ionic equation that shows all water-soluble reaction components as free ions 3. Identify and cancel any ions that appear on both sides of the equation 4. Check to ensure that all atoms and charges are balanced
Match the concentrations below with the correct bodily fluid location. 1. Na+ 135 meq/L 2. K+ 125 meq/L 3. K+ 4.0 meq/L 4. Na+ 10 meq/L
1. in blood and intracellular fluid 2. in intracellular fluid 3. in the blood & intercellular fluid 4. in the intracellular fluid
A sodium chloride solution that is 1-% (m/v) contains
10 g of sodium chloride for every 100mL of solution
When the coefficient "4" precedes the reactant NaClO3 in a balanced chemical equation, there are _____ oxygen atoms
12 (4 x 3 = 12)
Which of the following gives the correct mathematical operation to calculate the number of molecules in 2.0 mol of CH4?
2.0 mol x 6.022 x 10^23 molecules/ 1 mol
How many moles of Au corresponds to 1.52 x 10^24 Au atoms? Avogadros number is 6.02 x 10^23
2.52
One formula unit of KOH of ______ amu; hence 1 mol of KOH has a mass of _____g. Read atomic masses to four significant figures before adding the together.
56.11 ; 56.11 (39.10 + 16.00 + 1.008 = 56.108, which rounds to 56.11)
Predicting the Extent of Radioactive Decay
A patient receives 10.0 ng of a radioisotope with a half-life of 12 hours. How much will remain in the body after 2.0 days, assuming radioactive decay is the only path for removal of the isotope from the body. • Calculate n, the number of half-lives elapsed using the half-life as the conversion factor: n = 2.0 days x 1 half-life / 0.5 days = 4 half lives
What is an acid-base reaction?
A reaction in which an H+ ion is transferred from one reactant to another
Which of the following gives the correct net ionic equation for the process represented below? AgNO3(aq)+KBr(s)+ KNO3(aq)
Ag^+(aq)+Br(aq)->AgBr(s)
Balanced the unbalanced equation below, using lowest possible whole-number coefficients, then match each substance to the correct coefficient as indicated. Al2S3(s)+H2O(l)->Al(OH)3(aq)+H2S(g) Al2S3 - H2O - Al(OH)3 - H2S -
Al2S3 - 1 H2O - 6 Al(OH)3 - 2 H2S - 3
Nuclear Power
Albert Einstein's Equation: E = mc2 energy (E) is the product of mass (m) times the speed of light (c) - A very large amount of kinetic energy can be formed from a small amount of matter • Release this kinetic energy convert liquid water into steam The steam drives an electrical generator producing electricity
What is the concentration of a solution formed by diluting 50.0 mL of 16 M acetic acid (HC2HO2) solution to 1.5 L?
Answer: 0.53 Worked Out: M2 = M1V1/V2 = (16M)(50.0 mL)/1500mL = 0.53 M
Calculate the molarity of a solution made from 32.50 g of sodium acetate (82.03 g/mol) in 250 mL of solution.
Answer: 1.6 M 'Work: M = mol solute/L of solution ->> 0.3962 mol/0.25 L = 1.6 M
How many atoms are combined in 3.46 moles of helium
Answer: 2.08 x 10^24 helium atoms Work: 3.46 molHe x 6.022 x 10^23 He atoms/ 1 mol He =2.08 x 10^24 He atoms.
A 20% (m/m) saline solution contains 5.0 g of NaCl. How many grams of water are present in the solution?
Answer: 20, g of water Explanation: 20.% = (5,0g/ x) x 100%, Rearranged: o.20x = 5.0g, x = 5.0g/ .20, x = 25g of solution, Therefore, there are 20.g of water (25g - 5.0g) in the solution
How many moles of water are contained in 1.99 x 10^26 molecules of water?
Answer: 3.31 x 10^2 moles of water Work: 1.99 x 10^26 molecules x 1 mol/6.02 x 10^23 molecules = 331 moles
When 2 mol of NaCl is dissolved in a sample of water, a total of ____ mol of particles will be present in the solution.
Answer: 4 Info: For every mol of compound that dissolves, 2 mols of particles dissociate into ions
A certain amount of a salt was added to a solvent in a flask. Most of the salt dissolved completely, but a small portion of the salt remained as a solid and settled to the bottom of the flask. The solution prepared would be characterized as a _____ solution.
Answer: Saturated Info: Recall that a saturated solution contains all of the solute that can be dissolved at a particular temperature. Any excesses solute added will not dissolve.
Which of the following can never be done when balancing a chemical equation?
Change the subscripts in a formula of a reactant or product
Which of the following can never be done when balancing a chemical equation?
Change the subscripts in a formula of a reactant or product.
The process in which solute or solvent particles move from an area of higher concentration to lower concentration is called
Diffusion
Gamma Production
Gamma radiation occurs to increase the stability of an isotope • The energetically unstable isotope is called a metastable isotope "m" - The atomic mass and number do not change - Usually gamma rays are emitted along with alpha or beta particles
Which of the following substances are the products in this chemical reaction. CH3CH2OH(l)+3O2(g)->2CO2(g)+3H2O(g)
H2O & CO2
Which are the two major ions found in blood?
HCO3 & Cl+
Which of the following substances would you expect to be soluble in water? FLIP THIS CARD NO QUESTION!!
KCI - is ionic and water soluble Methanol (CH3OH) - Methanol is a small polar molecule that can hydrogen bond with water molecules.
Which equation correctly defines molarity?
M = moles of solute (mol)/volume of solution (L)
Bleaching
Most bleaching agents are oxidizing agents
In order to balance the reaction of hydrogen gas (H2) with oxygen gas (O2) to form liquid H2O, a student adds a subscript of 2 H2O (forming H2O2). Is this an acceptable method of balancing the reaction described?
NO! Formulas of species involved in chemical reactions should never be changed, because this changes the identity of the compound. Only coefficients should be added to balance chemical equations.
In order to balance the reaction of hydrogen gas (H2) with oxygen gas (O2) to form liquid H2O, a student adds a subscript of 2 to H2O (forming H2O2). Is this an acceptable method of balancing the reaction described?
NO!! Formulas of species involved in chemical reactions should never be changed, because this changes the identity of the compound. Only coefficients should be added to balance chemical equations.
Which two ions are the most important cations in body fluids?
Na+ & K+
Important Factors for Stable Radioisotopes
Nuclear stability correlates with the ratio of neutrons to protons • For light atoms a ratio of 1 is typically stable - Nuclei with large number of protons (84 or more) tend to be unstable - Isotopes with a "magic number" of 2, 8, 20, 50, 82, or 126 protons or neutrons are stable; this seems to indicate energy levels within the nucleus - Isotopes with even numbers of protons or neutrons are generally more stable than those with odd numbers of protons or neutrons - All isotopes (except 1H) with more protons than neutrons are unstable; the opposite is not true
Match the term with the correct definition: Oxidation - Reduction -
O - A process that involves the loss of electrons, loss of hydrogen atoms, or gain of oxygen atoms R - A process that involves the gain of electrons, gain of hydrogen atoms, or loss of oxygen atoms
Rem (Roentgen Equivalent for Man)
Obtained by multiplication of the rad by a factor called the relative biological effect (RBE) • RBE = 10 for alpha particles • RBE = 1 for beta particles
The solubility rule "like dissolves like" refers to which one of the following properties of compounds?
Polarity
Rad
Radiation absorbed dosage • The dosage of radiation able to transfer 2.4 x 10^-3 cal of energy to 1 kg of matter
When the following chemical equation is balnced correctly, what is the correct coefficent for each species? (Enter all the numbers, including the digit 1, if required.) SO2(g)+O2(g)->SO3(g)
SO2 - 2 O2 - 1 SO3 - 2
Radiation Exposure
Shielding • Alpha and beta particles need low level of shielding: lab coat and gloves • Lead, concrete or both required for gamma rays Distance from the Radioactive Source • Doubling the distance from the source decreases the intensity by a factor of 4 Time of Exposure • Effects are cumulative Types of Radiation Emitted • Alpha and beta emitters are generally less hazardous then gamma emitters Waste Disposal • Disposal sites are considered temporary
What information is contained in a chemical formula?
The identity of the elements present in a substance. The relative number of each type of atom
Which statement describes the effect of mixing a nonvolatile solute with a liquid solvent on the freezing point of a solution?
The solution has a lower freezing point than the solvent alone.
Which of the following correctly describes the formula mass of a compound
The sum of the atomic masses of all the elements in the compound
The Magnitude of the Half-Life
There are issues involved when using isotopes with a short half-life • Disadvantage: larger amount of radioactivity per unit time• Advantage: if accident occurs, reaches background radiation levels more rapidly
Predicting Products of Nuclear Decay
To predict the product, simply remember that the mass number and atomic number are conserved
Positron Emission
Unlike beta decay, the product nuclide has the same mass number as the parent BUT the atomic number has decreased by one.
Which statement about a solution of rubbing alcohol that is 30% isopropanol & 70% water is correct?
Water is the solvent
Calculate the number of moles of solute in 2.0 x 10^2 mL of 0.30 M acetic acid (CH 3CO2H).
Worked Out: mol = M x V = 0,30 M x 0.20 L = 0.060 mol
buffer capacity
a measure of the ability of a solution to resist large changes in pH when a strong acid or strong base is added
Artificial radioactivity
a normally stable, nonradioactive nucleus is made radioactive Made in two ways: • In core of a nuclear reactor • In particle accelerators - small nuclear particles are accelerated to speeds approaching the speed of light and slammed into another nucleus
Amphiprotic
a substance possessing both acid and base properties
Gray
absorption of 1 J of energy by 1 kg of matter
The formula mass of a compound expressed in ________ is numerically the same as the mass of one mole of the compound expressed in ________.
amu; grams
The mass of one-twelfth of a carbon-12 atom is 1.661 x 10-24 g. This quantity is known as one _______
atomic mass
The mass of one-twelfth of a carbon-12 atom is 1.661 x 10^-24 g. The quantity is know as one __________ unit.
atomic mass
The law of conservation of mass states that matter can be neither created nor destroyed in a chemical process. Therefore any chemical reaction that we write must be _________.
balanced
The conversion of potassium chlorate to potassium chloride and oxygen is an example of a ________ change.
chemical
conjugate acid-base pair
consists of two substances related by the loss or gain of a single hydrogen ion
The solubility of gases ______ with increasing temperature.
decreases
The process by the kidneys to remove excess waste from the blood is called _______
dialysis
The equivalent unit for an ion corresponds to the number of grams of ion in relation to Avogadro's number of ______.
electrical charges
Voltaic cell
electrochemical cell that converts stored chemical energy into electrical energy
Beta particle (β)
fast-moving electron• Emitted from the nucleus as a neutron is converted to a proton• Higher speed particles, more penetrating than alpha particles
The higher the pressure of a solute gas above a solution, the ________ the solubility of the gas in the solvent.
higher
A true solution is a ______mixture with uniform properties throughout.
homogenous
In acid base chemistry, a proton is an ________ atom that has lost its electron. Thus it is an ion that has the symbol _______, and not a proton from the nucleus of an atom.
hydrogen or H; H+
Arrhenius acid
is any species that increases the concentration of H+start text, H, end text, start superscript, plus, end superscript in aqueous solution
A nonvolatile solute is dissolved in water to form a solution. The vapor pressure above the solution is _______ than the vapor pressure of pure solvent.
lower
(Nuclear Medicine) Nuclear imaging
medical techniques involving tracers Example: • Iodine concentrates in the thyroid gland. • Using radioactive 131I and 125I will allow the study of how the thyroid gland is taking in iodine
For an element, the mass of Avogadros number of atoms is known as the _______ mass.
molar
Molarity (m) is defined as the number of ______ of solute per ______ of solvent.
moles; kg
Solution of ______ are typically formed from soluble molecular compounds, whereas solutions of ______ are formed from soluble ionic compounds.
nonelectrolytes; electrolytes
Which of the following provides the correct mathematical operation to convert the number of atoms of a sample to the number of moles.
number of atoms DIVIDED BY Avogadros number
weak acid
one which does not dissociate 100%
The diffusion of a solvent through a semipermeable membrane in response to a concentration gradient is called _________.
osmosis
Measuring pH
pH of a solution can be: • Calculated if the concentration of either ion is known • Approximated using indicator / pH paper that develops a color related to the solution pH • Measured using a pH meter whose sensor measures an electrical property of the solution that is proportional to pH
Osmolarity is defined as the molarity of ________ in solution.
particles
Radioactivity
process by which atoms emit energetic particles or rays
Ionizing radiation
produces a trail of ions throughout the material that it penetrates • The penetrating power of the radiation determines the ionizing damage that can be caused • Alpha particle < beta particle < gamma rays
Gamma Rays (ɣ)
pure energy (electromagnetic radiation) - Highly energetic - The most penetrating form of radiation -Symbolized as:
alpha decay
radioactive decay by emission of an alpha particle -The top number (mass numbers) must balance 238 = 234 + 4 - The bottom numbers (atomic numbers) must balance 92 = 90 + 2
In a chemical reaction, the starting materials are called _______.
reactants
pH scale
scale with values from 0 to 14, used to measure the concentration of H+ ions in a solution; a pH of 0 to 7 is acidic, a pH of 7 is neutral, and a pH of 7 to 14 is basic
(Nuclear Medicine) Tracers
small amounts of radioactive substances used as probes to study internal organs
buffer solution
solution which resists large changes in pH when either acids or bases are added
Osmotic pressure is the pressure that prevents the flow of additional ______ into a solution on one side of a semipermeable membrane
solvent
The dilution of a solution involves the addition of _______ to decrease the concentration of _______.
solvent; solute
The molecular mass of a compound is the ______ of the atomic masses of the elements in one ______of the compound.
sum; molecule
Lethal dose (LD50)
the acute dosage of radiation that would be fatal for 50% of the exposed population • LD50 = 500 rems
Becquerel
the amount of radioactive material that produces 1 atomic disintegrations per second
Curie
the amount of radioactive material that produces 3.7 x 10^10 atomic disintegrations per second
Corrosion
the deterioration of metals caused by an oxidation-reduction process
Radiocarbon dating
the estimation of the age of objects through measurement of isotopic ratios of carbon • Ratio of carbon-14 and carbon-12 Basis for dating: • Carbon-14 (a radioactive isotope) is constantly being produced by high-speed neutrons from cosmic radiation
A chemical change must involve _______
the formation of new substances
conjugate acid
the particle formed when a base gains a hydrogen ion
conjugate base
the particle that remains when an acid has donated a hydrogen ion
ion product constant for water
the product of the concentrations of hydrogen ions and hydroxide ions in water (kw)
Chain reaction
the reaction sustains itself by producing more neutrons
Half-life (t1/2)
the time required for one-half of a given quantity of a substance to undergo change - Each radioactive isotope has its own half-life • Ranges from a fraction of a second to a billion years • The shorter the half-life, the more unstable the isotope
Nuclear medicine:
the use of radioisotopes in the diagnosis of medical conditions
Nuclear equation
used to represent nuclear change - When writing a balanced equation, remember that: • the total mass on each side of the reaction arrow must be identical • the sum of the atomic numbers on each side of the reaction arrow must be identical
Electrolysis
uses electrical energy to cause nonspontaneous oxidation-reduction reactions to occur
An aqueous solution is one in which ______ is the solvent.
water
Positron
• Has the same mass as an electron, or beta particle • Has an opposite charge of an electron (+) • Symbolized as: