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hydrogen bonds b sonpolar covalent bond c. polar covalent bonds E. van der Waals

ID: 146293 • Letter: H

Question

hydrogen bonds b sonpolar covalent bond c. polar covalent bonds E. van der Waals interactions d. ionic bonds 43. The slige What is oegative charge at one end of one water molecule is atracted to the slight positive charge of another water molecule. What s this attraction called? a covalent bond a hydirogem bond c an ionic bond The breaking of bonds between water molecules Water molecules absorb heat from the surface in order to acquire enough energy d a polar ceovalent bond e van der Waals interactions 44. Why does evaporation of water in sweat from the skin cause cgoling ofurfce a absorbs heat b. The water molecules with the most heat energy evaporate more readily c. The solute molecules left behind absorb heat to evaporate e. The expansion of water vapor extracts heat from the surface le oils are which of the following? a nonpolar substances that repel water molecules nonpolar substances that have an attraction for water molecules c. polar substances that repel water molecules d. polar substances that have an affinity for water e charged molecules that hydrogen-bond with water molecules 46. How many grams would be equal to 1 mole of fructose (C.H:O)? 6.02 X 10h grams b. 75 grams c.90 grams d. 150 grams 180 grams One mole of glucose consist of which of the following? a. 180 1023 molecules of glucose b. lkg of glucose dissolved in I L of solution 47. the largest amount of glucose that can be dissolved in 1 L of solution 1 80 kilograms of glucose both 180 grams of glucose and 6.021023 molecules of glacose 48. How many moleculs of glycerol (CyHgos, molecular mass 9),would be present in I L of a L M.plycerol solution? 0.14 602 1023 92 602 1023 d6.02 102602102 49. A strong acid like HCI does which of the following? a ionizes completcly in an aqueous solution b. increases the pH when added to an aqueous solution c. reacts with strong bases to create a buffered solution is a strong buffer at low pH both ionizes completely in aqueous solutions and is a strong buffer at low pH 50. Which of ing ionizes completely in solution and is considered to be a strong base (alkali)? 51. Buffers are substances that help resist shifts in pH by b. c. d. e releasing H+ to a solution when acids are added donating H+ to a solution when bases are added releasing OH to a solution when bases are added accepting H+ from a solution when acids are added both donating H + to a solution when bases are added, and accepting H. when acids are added 52. If a solution has a pH of 7, this means which of the following? a. there are no Ht ions in the water b. this is a solution of pure water the concentration of H+ ions in the water equals the concentration of°H-ions in the water d. this is a solution of pure water, and the concentration of Ht ions in the water is 10-7 M

Explanation / Answer

I will be indicating the questions which have been answered wrong.

49. a. ionises completely in aqueous solution (a buffer is a mixture of weak acid and a conjugate base or vice cersa that helps in maintaining slight pH changes. A strong acid however does not have this property can cannot maintain fluctuations of pH.)

50. e. NaOH (what you have indicated is an acid and the question asks for alkali i.e. base)

51. e. both donating H+ when base is added and accepting H+ when acid is added.

Being a buffer, this solution will balance the pH both in case an acid or a base is added to the buffer by donating or accepting the H ions.

All the other answers are correct. All the Best :)