Molecules of Life

Which of the following properties is an intensive physical property?

In Lab 1, you performed chemical tests to determine who else had the sam substance you had. Which of the following properties of a substance is classified as a chemical property

What is the definition of a compound?

When an electrical current is passed through water, two colorless gases ar produced as shown in the photograph. What change is taking place?

The chemical elements in the second period of the periodic table forms bonds with hydrogen atoms according to the following formulas: CHa NHs H2O HF Predict the chemical formula of the molecule formed when arsenic (As) reacts with hydrogen

Deduce the identity of the chemical element X based on the following clues. • K reacts with chlorine to form X Cl4 • The most abundant isotope of X has a mass number of A = 28

Which of the following elements has 7 valence electrons?

What type of electron orbital is depicted by the shape below?

Identify the Chemical Element below based on its electron configuration. Write the full name and chemical symbol for the element.

This goes with question 9: What type of ion will this atom form? Explain your answer

Many atoms form an ion by gaining or losing one or more electrons. For each of the atoms below: • Draw the electron configuration using the electron shell model. Include all the electrons in the atom and the shells where these electrons are located. Use the electron configuration to predict the type of ion that the atom will form. Write the chemical formula for the ion in a way that indicates its net electrical charge. (a) Fluorine (F) (b) Aluminum (AI)

Disulful gas has the chemical formula S2. What type of bond is used to join the two S atoms?

What principle is used to predict the three-dimensional structure of molecules? Provide the full name and a brief explanation.

In Lab 3, you used a computer program to investigate the structure of a theoretical molecule. The diagram below shows a screenshot from this computer program.

How will the molecule geometry be affected by adding one lone pair to the central atom? Draw a ball-and-stick molecular model of the molecule and include the lone pair as a "balloon." What is the name f this molecular shape?

Chloroform is a liquid substance that was commonly used as an anesthetic in the 19th and early 20th Century. The molecular formula for chloroform is CHCIx, where you will deduce the numerical value of x. (a) Draw the Lewis dot structure of this molecule (b) Based on your answer to Part (a), deduce the chemical formula of this molecule (c) Draw the 2D structure of the molecule, showing covalent bonds and all lone pairs. (d) Draw the 3D structure of the molecule using the wedge-and-dash notation. Include all lone pairs

Draw a space-filling molecular model of the molecule that accurately depicts the atomic radius of each atom. Label each atom in the model with the appropriate chemical symbol.

(a) Draw the Lewis dot structure for HCN. What type of bond joins the C and N atoms in this molecule?

(b) Draw the two-dimensional structure for HCN, showing covalent bonds and all lone pairs.

(c) Predict the three-dimensional shape of this molecule and draw it below. Include all lone pairs.

An alkane hydrocarbon contains __________ covalent bonds.

Octane is an alkane hydrocarbon that contains 8 carbon atoms. You are familiar with this molecule from the "octane rating" of gasoline when you fill up your car. Based on what you know about alkane hydrocarbons, deduce the chemical formula for octane.

What term describes the replication mechanism proposed by Watson and Crick?

component of nucleotide

The Nobel Prize in Physiology or Medicine was awarded in 1962 for discovering the structure of DNA. Which scientists won the Nobel Prize (full names)? Was Rosalind Franklin considered as a candidate for this Nobel Prize? Explain.