Exam 2: Essential Chemistry for Biology

Human body cells are approximately ________ water.

Relative to a pH of 6,a pH of 4 has a ________.

How do radioactive isotopes differ from isotopes?

Please read the following scenario to answer the following questions. While radioactive isotopes are used in medicine to identify tumors and other diseases, they can also be used to treat diseases such as cancer. One method to treat cancerous tumors is to expose them to radiation, which can kill the cancerous cells and the tumor. In 2013, the U.S. Food and Drug Administration approved a new cancer treatment based on the radioactive isotope radium-223; this isotope has a half-life of 11.4 days. The radioactive drug, known as Xofigo, is injected into the patient's bloodstream and travels to certain regions of the body. Because it emits high-energy radiation over short distances, it can kill cancerous cells in the sites where it localizes. After the drug was injected into a person, the following data were collected regarding the amount of radiation measured in different organs in the person's body. -Using the table above,what kind of cancer do you think Xofigo is used to treat?

In the following reaction,what type of bond is holding the two atoms together? K+Cl → K⁺ + Cl− → KCl

The way Earth moves about the sun is most like ________.

Isotopes of an element have the same number of ________ and different numbers of ________.

As water freezes,________.

All atoms of an element have the same number of ________.

The hydrogen and oxygen atoms of a water molecule are held together by ________ bonds.

Please read the following scenario to answer the following questions. The last few miles of the marathon are the most difficult for Heather. Her hair is plastered to her head, sweat clings to her arms, and her legs feel as if they had nothing left. Heather grabs a cup of ice water. The ice cubes smash against her nose as she gulps some cool refreshment and keeps on running. Then a breeze kicks up and she finally feels some coolness against her skin. Drops of sweat, once clinging to her forehead, now spill down, and Heather feels a stinging as the sweat flows into her eyes. -When Heather grabbed the glass of ice water,the ice cubes were floating at the top.Why were the ice cubes floating in the water?

What are the reactant(s)in the following chemical reaction? C₆H₁₂O₆ + 6 H₂O + 6 O₂ → 6 CO₂ + 12 H₂O

The lower the pH of a solution,the ________.

Beryllium's atomic mass is 9,and its atomic number is 4.How many neutrons are found in a beryllium atom?

What name is given to bonds that involve the sharing of electrons?

An atom's ________ are found in its nucleus.

The bond between oppositely charged ions is a(n)________ bond.

An uncharged atom of gold has an atomic number of 79 and an atomic mass of 197.This atom has ________ protons,________ neutrons,and ________ electrons.

Sulfur has an atomic number of 16.How many covalent bonds can sulfur form?

Please read the following scenario to answer the following questions. The last few miles of the marathon are the most difficult for Heather. Her hair is plastered to her head, sweat clings to her arms, and her legs feel as if they had nothing left. Heather grabs a cup of ice water. The ice cubes smash against her nose as she gulps some cool refreshment and keeps on running. Then a breeze kicks up and she finally feels some coolness against her skin. Drops of sweat, once clinging to her forehead, now spill down, and Heather feels a stinging as the sweat flows into her eyes. -Why did the sweat on Heather's forehead and arms form drops?