Which of the following describes a substance in the solid physical state? The substance compresses significantly. The substance has a variable volume. The substance has a variable shape. all of the above none of the above
Which of the following is an example of a physical change? changing color releasing heat forming an insoluble solid dissolving a substance none of the above
Which of the following processes produces a decrease in the entropy of the system? D dissolution of solid KCI in water D melting ice to form water D boiling water to form steam mixing of two gases into one container D freezing water to form ice
Only about 25% of useful energy is produced in combustion (cars) True False
Question 2 Describe the difference between molecular and ionic compounds. square
Mixture A was made by mixing different components together but it appears to have one phase. Which term best categorizes mixture A? colloid solution emulsion suspension
Which of the following are the reactants of the chemical equation 2H_(2)+O_(2)... 2H_(2)O O_(2) C_(3)H_(13) H
Hexane, C_(6)H_(14) would have which of the following fragments in its mass spectrum? Check all that apply. (m)/(z)=32 (m)/(z)=57 (m)/(z)=29 (m)/(z)=43
Which neutral atom has the following electron configuration: 1s^22s^22p^63s^23p^64s^23d^104p^65s^24d^105p^66s^2 Enter the chemical symbol for the element. View Available Hint(s)
Calculate the density in grams per liter of HF at STP. Be sure your answer has the correct number of significant figures. Note: For molar mass calculations, round to the hundredths place. square (g)/(L)
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
