B) decreased enthalpy of the system. C) increased entropy of the water molecules. D) very strong van der Waals forces among the nonpolar molecules or groups. Answer: C Page Ref: Section 5 29) Water clustered about nonpolar molecules contribute to hydrophobic interactions
Name: ___________________________________ Date: ______________ Practice Test #3 ____ 1. When a precipitation reaction occurs, the ions that do not form the precipitate A) evaporate B) are cations only C) form a second insoluble compound in the solution D) are left dissolved in the solution E) none of these 2. An aqueous solution of potassium chloride is mixed with an aqueous solution of sodium nitrate. The complete ionic equation contains which of the following species (when balanced in standard form)? A) B) C) D) E) ____ 3.
dispersion forces occur frequently for short periods of time. Dipole force - this permanent force operates between polar molecules. - a polar molecule has regions of positive and negative charge. Hydrogen bond - highly polar bond capable of producing a strong dipole force between molecules. the dipole attraction is typically about 10% of the strength of a normal covalent
D) It conducts electricity when dissolved in water. E) none of the above 4. In a Lewis dot structure the electrons which complete an octet but are not located between two atoms are referred to as A) bonding pairs. B) delta minus electrons. C) excess electrons.
Although some subatomic particles have a greater mass than some atoms. Subatomic particles are made of quarks such as a proton which is made of two up quarks and one down quark. The atom is a basic unit of matter that consists of a dense nucleus surrounded by negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons. The electrons of an atom are bound to the nucleus by the electromagnetic force.
How many multiple bonds (double and/or triple) are there in this molecule? (1 point for each molecule) There are no double or triple bonds on this molecule. CO2 4+2(6)=16 .. .. O = C = O .. .. 1. What is the central atom? (1 point for each molecule) The central atom is C. 2.
4) When naming an ionic compound, which ion is given first? The metal ion is named first 5) Give explanations for the following: a. Argon will not react with any other element It already has a complete number of eight, a full number in its valance shell so it cannot react with itself or another element b. The reaction between sodium chloride gives out a lot of heat and light. The chemical energy of the product is less then the chemical energy of the reactants. This energy is indestructible and is converted to light and heat.
Neutrons, Protons and electrons are all sub-atomic particles. In relative mass, we always think of protons and neutrons in having a mass of 1 and electrons a mass of 1/1840, which shows that electrons are considerably smaller than protons and neutrons, and only make up a small part of the atom. The amount of protons and neutrons added together is the relative atomic mass, and this is the main structure of the atom. 2. The arrangement of particles in an atom Protons and neutrons make up the main, dense, central nucleus in the centre of the atom.
A. III and IV B. IV only C. II and IV D. III only 2. Which formula(s) describe an alkane? A. III only B. V only C. I and V D. none of the above 3. Which formula(s) describe an alkene? A. I only B. V only C. I and V D. III only 4.
Which of these physical changes would require the liberation of energy? a. condensation of steam to form liquid water b. melting of ice c. boiling of water d. all of the above e. none of the above ____ 5. Which answer lists all the substances below that are compounds and not any elements or mixtures? I. II. III.