Chapter 2-Chemistry of Life

Which of the following pH values would be considered weakly basic? 5.3 8.2 12.4

8.2

When hydrogen is involved in a polar covalent bond, it has a ________.

A slight positive charge

In an ionic bond, the charge on the cation is ________.

Always positive

Chlorine is in group 17 of the periodic table and is very reactive, why is that? Because Chlorine has a perfect set of 8 valence electrons and abides by the octet rule. Because chlorine is flammable. Because chlorine has 7 valence electrons in its outer shell like the rest of the halogens and is very reactive because it wants to obtain 8 total valence electrons to be stable.

Because chlorine has 7 valence electrons in its outer shell like the rest of the halogens and is very reactive because it wants to obtain 8 total valence electrons to be stable.

Given the characteristics of ionic bonds, which of the following would Potassium, K, most readily form an ionic bond with? Bromine (35) Sodium (11) Aluminum (13) Neon (10)

Bromine

Which elements have only one electron shell? helium carbon hydrogen

Helium & Hydrogen

Which of the following is a correct statement? Covalent bonds lead to molecules that are stable in air while ionic bonds do not. Ionic bonds to do not share valence electrons while covalent bonds do. ​Covalent bonds only occur between atoms of similar electronegativities while ionic bonds only occur between atoms of differing electronegativities.

Ionic bonds to do not share valence electrons while covalent bonds do.

Select the bond that is most polar. N=N O=C O-H

O-H

Carbon-12 and Carbon-13 are two examples of carbon isotopes. They have the same number of _____, but different numbers of ____.

Protons/Neutrons

There are several types of bonds found in nature but one is the weakest. This type of bond only forms very weak and temporary bonds between molecules. What types of bonds are these? Covalent bonds Ionic bonds Hydrogen b Van der waals interactions

Van der waals interactions

Which of the following is NOT a property of water? Water dissolves hydrophobic substances easily Water expands when it freezes Water molecules have the tendency to stick together

Water dissolves hydrophobic substances easily

Maria works as a chemist in a research laboratory. She received a call today from the local waste disposal facility about a barrel of unidentified solution and has been asked to help identify it as an acid, base, or neutral solution so that it can be properly disposed of. After taking a sample of the solution to study in her lab she has found out the following information: The solution has a pH of 11, is slippery to the touch, and readily donates OH- molecules when dissolved in water. What type of solution is Maria working with? A neutral solution There is not enough information to categorize this solution An acid A base

a base

In nature we can find a variety of bonds that hold atoms and compounds together. What type of weak bond can you find in your own DNA as well as between individual water molecules? A non-polar covalent bond An ionic bond A hydrogen bond A polar covalent bond

a hydrogen bond

Which of the following is an example of van der Waals force? a hydrogen bond an ionic bond a polar bond

a hydrogen bond

In an ionic bond, the charge on the cation is ________. always negative either negative or positive always positive

always positive

Basic pH is maintained in which of the following? gastric "juices" blood Ammonia solutions

ammonia solutions

Which of the following best explains the natural formation of ions? an unfilled outer electron shell and electron transfer a filled outer electron shell and a large electronegativity differential an unfilled outer electron shell and electron sharing

an unfilled outer electron shell and electron transfer

A common household example of a buffer is ________. lemon juice antacid Bleach

antacid

A(n) ________ is the smallest unit of matter that retains all the properties of an element. atom proton electron

atom

________ are composed of a nucleus and an electron shell. Atoms Cells Neutrons

atoms

Baking soda has a(n) ________ pH. acidic near-neutral basic

basic

________ function by absorbing excess hydrogen or hydroxide ions. Buffers Acids Bases

buffers

________ in the body affect blood pH by creating bicarbonate when the pH needs to be lowered. Acids Buffers Bases

buffers

Pick the most complete answer. All living organisms contain ________. carbon carbon and oxygen carbon, oxygen, hydrogen, and nitrogen.

carbon, oxygen, hydrogen, and nitrogen

In table salt, the anion is ________. sodium the full compound chloride

chloride

When acids are added to a solution, the pH should ________. stay the same decrease Increase

decrease

An atom's________ are disregarded when calculating its mass. electrons protons neutrons

electons

Which type of bond enables many of the properties of water? polar covalent bond nonpolar covalent bond hydrogen bond

hydrogen bond

Which type of bond represents a weak chemical bond? ionic bond covalent bond hydrogen bond

hydrogen bond

Ultimately, excess ________ build up in the body is prevented by the exhalation of carbon dioxide. bicarbonate hydrogen ions hydrogen atoms

hydrogen ions

One of the following is a reason why water important for life: It is a cohesive substance. It provides energy for life It is found everywhere.

it is a cohesive substance

Which of the following is a reason why water important for life? It is found everywhere. It is the major organic molecule for life. It is a universal solvent.

it is a universal solvent

Argon (Atomic number 18) has more than one electron shell and the outermost shell contains eight electrons. What is the outcome of such electron configuration? It is stable and inert It forms covalent bonds in an aqueous solution. It becomes extremely unstable and reactive.

it is stable and inert

Neon (Atomic number 10) has more than one electron shell and the outermost shell contains eight electrons. What is the outcome of such electron configuration? It becomes extremely unstable and reactive. It is stable and inert It forms covalent bonds in an aqueous solution.

it is stable and inert

Blood maintains a ________ pH. basic near-neutral acidic

near-neutral

Mrs. Brown has set up a trivia game for her students to help them identify the types of bonds. The first team of students has been given the following clues about a compound and asked to identify what type of bonds are present between the elements of this compound: It is made up of two elements, these two elements are non-metals, and these two elements share electrons equally with one another. What is the correct answer to this trivia question? Polar covalent bonds Hydrogen bonds Ionic bonds Non-Polar covalent bonds

non-polar covalent bonds

The ________ of electrons controls how elements interact. number and arrangement size and arrangement size

number and arrangement

The most common element in humans is ________. oxygen nitrogen carbon

oxygen

Jamie is assigned a project where she must create a model of an atom using household objects. Jamie is brainstorming ideas for each part of the atom. What is located in the nucleus of an atom that Jamie must represent? Protons and neutrons Electrons Neutrons only Protons and electrons

protons and neutrons

Acids are substances that ________. release hydrogen ions absorb hydrogen ions absorb hydroxide ions

release hydrogen ions

Leslie and her lab mates are given an assortment of food and beverage based lab samples. They are asked to identify each sample as either acidic or basic and list all characteristics of that sample that helped them identify it as one or the other. Their first sample is lemon juice which they have determined to be acidic. Which of the following is NOT a characteristic of lemon juice they would have recorded in their data table? Slippery to the touch A pH of 2 Turned blue litmus paper red Sour to the taste

slippery to the touch

In table salt, the cation is ________. the full compound chloride sodium

sodium

Of all 118 elements present on the periodic table only 4 are considered common to every single living organism on earth. Which of the following is NOT one of those four elements? Hydrogen Sulfur Nitrogen Carbon

sulfur

Julia is playing softball in the summer and begins to sweat all over. What property of water is her body relying on? The ability of water to stabilize temperature The polarity of water The cohesiveness of water The solubility of water

the ability of water to stabilize the temperature

Double bonds form when ________ of electrons are shared. two pairs one pair three pairs

two pairs

Using a pH meter, you find the pH of an unknown solution to be 8.0. How would you describe this solution? strongly basic weakly basic weakly acidic

weakly basic