What is the molecular formula of a molecule that has an empirical formula of CH_(2)O and a molar mass of 120.12g/mol
State the number of valence electrons for each of the following elements. Sn square
What is the term for a pure substance that cannot be broken down any further by ordinary chemical reaction? homogeneous mixture element compound heterogeneous mixture none of the above
Which of the following groups of elements has the highest ionization energy? Group VIIA/17 Group VIIIA/18 Group IIB/12 Group IA/1 Group IIA/2
What is the current official name for element 108? hassium bohrium seaborgium dubnium none of the above
Which of the following is an example of a chemical change? charring sugar cooking a steak baking a pie boiling an egg all of the above
Which of the following is an example of a physical property? physical state melting point color crystalline form all of the above
What is the term for the weighted average mass of all the naturally occurring isotopes of an element? atomic mass atomic notation mass number atomic number none of the above
Which of the following is an inactive ingredient used as an occlusive skin protectant? Glycerin Lecithin Petrolatum Dimethicone
The solute particles that interfere with vaporization are: Select the correct answer below: in the middle of the solution at the surface of the solution in the gas phase none of the above
What is the major ion in seawater? sodium chloride magnesium sulfate
5. How can 100. mL of sodium hydroxide solution with a pH of 13.00 be converted to a sodium hydroxide solution with a pH of 12.00 ? (A) By diluting the solution with distilled water to a total volume of 200 mL (B) By diluting the solution with distilled water to a total volume of 1.00 L (C) By adding 100 mL of 0.10 MHCI (D) By adding 100 mL of 0.10 MNaOH
12. How does the concept of electron transfer explain why sodium and chlorine react to produce sodium chloride?(Hint: Think about the movement of electrons between sodium and chlorine atoms during the reaction.)
2. Use Passage 1 to answer question below. Suppose that in Experiment 2 a solution at a pH of 7.5 had been tested. Based on the results of Experiment 2, the percent recovery of cadmium for that solution would most likely have been: F. between $48\% $ and $80\% $ G. between $80\% $ and $88\% $ H. between $88\% $ and $95\% $ J. between $95\% $ and $100\% $ F G. H. J.
1.Use Passage 1 to answer question below. Based on the description of Experiment 1, when was the graphene separated from the sample liquid by centrifugation? A. Immediately before placing the sample in the water bath B. Immediately after removing the sample from the water bath C. Immediately before the percent recovery of the cadmium was determined D. Immediately after the percent recovery of the cad- mium was determined A B C D
Which statement about asbestos fibers is correct? A. All asbestos fibers are visible without magnification B. Asbestos fibers can be identified by color and texture alone C. Some asbestos fibers are extremely small and require laboratory testing to confirm their presence D. Asbestos fibers are always thicker than a human hair
Which of the following statements describes how water differs greatly from many other substances? It is less dense in its solid form than liquid form. It is a polar covalent molecule. It can change to solid liquid and gas phases. It is comprised of two different elements.
Name the following ionic compounds. Make sure you are in text mode $(''Tt'')$ Do NOT put a space between metal and charge in parentheses if naming a Type II metal ionic compound (i.e. iron(III)) a. $CoCl_{2}$ $\square $
3. How many grams of $Fe_{2}(SO_{4})_{3}$ will be produced from 4.25 moles of Fe? $2Fe+3H_{2}SO_{4}\rightarrow 1Fe_{2}(SO_{4})_{3}+3H_{2}$
Red litmus paper turning blue indicates the prescence of __ ? $Ni(II)$ $Ca(II)$ $Fe(III)$ Ammonium Ion
