2+ c. 3+ d. 1- e. 3- Page 13 73. What is the predicted ionic charge for a barium ion? a. 1+ b. 2+ c. 3+ d. 1- e. 2- 74.
Research the answers to the following questions on the internet and write your answers in your own words. For each answer, include the address of the web site (or title and author of a book or article) that you used to help you answer the question. 1. Which type of compound usually has higher melting points: ionic compounds or covalent compounds? What is the reason for this difference in melting points?
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.
A) ZnCH 3 CO 2 B) Zn(CH 3 CO 2 ) 2 C) Zn(HCO 3 ) 2 D) Zn(HCl) 8 14. Which chemical formula is not correct? A) Na 2 HCO 3 B) Na 2 HPO 3 C) Na 2 HPO 4 D) Na 2 SO 3 E) More than one of the above formulas is not
What determines the ratio of elements in an ionic compound? (i.e. why are NaCl in a 1:1 ratio but CaCl2 has a 2:1 ratio of elements?) 2. Two ionic compounds often react so that the positive and negative ions change places.
Note: these formulas would have been written in the upper right hand corner of each box before beginning the lab. 2) Examine your data to see if you can justify eliminating some of the combinations listed as possible precipitates in this experiment. For example, NaCl was an aqueous product in Set 1-15. Therefore it could not precipitate in another box or set. 3) Write equations to indicate what you consider to have happened in each case in which there was precipitate formed.
Ch. 18 5. A conducting sphere has a net charge of −4.8 ×10−17 C. What is the approximate number of excess electrons on the sphere? 22. Three identical point charges, Q, are placed at the vertices of an equilateral triangle as shown in the figure.
Kinetic vs. Potential Energy 2. Forms of Energy a. Chemical Energy b. Electrical Energy c. Mechanical Energy d Radiant Energy II.
Midterm #3 Practice Exam 1. The energy of a photon of light is __________ proportional to its frequency and __________ proportional to its wavelength. A. directly, inversely B. indirectly, not C. directly, directly D. inversely, inversely E. inversely, directly 2. What is the frequency of light (s-1) that has a wavelength of 1.23 x 10-6 cm? A.
Physics Project Julie Gay What is electricity, and how does it have anything to do with a battery or our body? According to “How Stuff Works”, “When you load a battery into an electronic device, you're not simply unleashing the electricity and sending it to do a task. Negatively charged electrons wish to travel to the positive portion of the battery -- and if they have to rev up your personal electric shaver along the way to get there, they'll do it. On a very simple level, it's much like water flowing down a stream and being forced to turn a water wheel to get from point A to point B.” So, what exactly does that mean to us? It means that electricity is a force that powers out world and our bodies (How stuff works, 2010).