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A graph is shown of the pressure of dinitrogen pentoxide, N2O5,  in a reaction vessel during a certain chemical reaction. Match the terms to the best estimate of the correct value.  Not all numbers will be used.  Hint:  count squares to estimate values.

Carbon dioxide gas is dissolved in water to make carbonated beverages.  If the pressure in a can of soda pop is increased, what happens to the amount of  CO2  that dissolves?

At 40°C, the vapor pressure of ethylene glycol is 120. Torr.  If  {U} moles of urea is mixed with {EG} moles of ethylene glycol, what will the new vapor pressure be for this mixture at 40°C?  Hint:  If your answer is smaller than 50, you have an error. Do not include the units in your answer.

Suppose that you combine the following three solutions/liquids in the same beaker:                   {X}. mL   0.40 M  KBr                   {Y}. mL   0.10 M  MgBr2                   20. mL   water What is the concentration of bromide anion, Br-, in the combined solution in M? Enter the number only, not the units. Do not use scientific notation.

The exchange rate display on a money changer office read:1 CAD = 0.660 EUR1 EUR = 1.66 AUD1 CAD = 0.740 USDA person spent [a] AUD for shopping in Australia. Based on the exchange rates provided above, how much money is it in US dollars (USD)? Report your final answer with 3 SFs. You must submit your scratch paper work to receive credit.

A conversion riddle includes the following conversion relationships:6 hats = 2 bats2 mats = 4 bats5 rats = 6 hatsHow many rats are equivalent to [p] mats? Make sure to show your work in the “box” setup. Report your answer as a whole number.You must show the box setup work (scanned copy of scratch papers) for credit.

Heat of fusion of water is 333 J/g. How many pounds (lb) of ice were melted if [a] kJ of energy was absorbed during the melting process? (Hint: Check units!)

What is the best answer to report for (48.5-46.16)20.21? To receive full credit, you must(a) mark the digits with uncertainties and follow the correct order of operations. (1 point)(b) apply appropriate significant figures rules (note that are different rules for addition/subtraction and multiplication/division). (1 point)(c) apply rounding rules before you write the final answer (make sure to avoid rounding errors and show your complete work on scratch paper). (2 points)Enter your final in the text box provided and show your work on scratch paper.

How many significant figures (sig. figs.) are in the following measurements? (A) 2.5000 km = [BLANK-1] sig. figs. (B) 0.0020 s = [BLANK-2] sig. figs. (C) 5200 mi = [BLANK-3] sig. figs. (D) 2002 L = [BLANK-4] sig. figs. (E) 0.05 g = [BLANK-5] sig. figs.

Hiram Bingham III, a historian-explorer who rediscovered Machu Picchu, and Leonardo Da Vinci, one of the greatest Renaissance exponents, have something in common. Choose the sentence that best describes this commonality.