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Questions in chemistry

[Answered] Which energy change occurs during boiling? A. Some heat energy of the substance is lost. B. Heat energy of the substance remains the same. C. Most heat energy of the substance is lost. D. Heat energy is absorbed by the substance.

[Answered] What happens in an acid-base reaction according to the Arrhenius definition? A. An acid accepts an electron pair from a base. B. An acid donates an H, and a base donates an OH. C. An acid donates an H, and a base accepts an H. D. An acid donates an H, and a base donates electrons.

[Answered] Select all the correct answers. The electron configurations of some elements are given. Based on the electron configurations, which elements can likely form ions with multiple charges? zinc $[ Ar ] 3 d^{10} 4 s^2$ Iron $[ Ar ] 3 d^6 4 s^2$ sodium [ Ne ] $3 s^1$ cobalt $[A r] 3 d^7 4 s^2$ silver $[ Kr ] 4 d^{10} 5 s^1$

[Answered] What is assumed to be constant when using the combined gas law? A. pressure B. number of moles C. volume and moles of gas D. pressure and temperature

[Answered] Which chemical symbol is properly written? a) CA b) Cu c) co d) CL

[Answered] Which of the following is an example of an Arrhenius acid? A. [tex]$BF _3$[/tex] B. [tex]$NH _3$[/tex] C. D. NaOH

[Answered] How many grams would [tex]$3.36 \times 10^{23}$[/tex] molecules of copper (II) sulfate ([tex]$CuSO_4$[/tex]) weigh? A. [tex]$5.55 g$[/tex] B. 89.03 g C. 8.903 g D. 0.5578 g

[Answered] A sample of water with a mass of 648.00 kg at 298 K is heated with 87 kJ of energy. The specific heat of water is [tex]$1 J-1 kg K -1$[/tex]. What is the final temperature of the water? A. 298.00 K B. 298.13 K C. 432.26 K D. 134.26 K

[Answered] You reacted 3.5 g of Zn with 75 ml of 0.70 M HCl originally at 23 C and the final temperature of the mixture was 45 C. What is the [tex]$\Delta H_{rn}$[/tex] per mole of zinc reacted? (Check how much Zn reacted, i.e. it may not be limiting)

[Answered] What is shown in the table?