A typical blood pressure in a resting adult is "120 over 80", meaning 120.0 mmHg with each beat of the heart (systolic) and 80.0 mmHg of pressure between heartbeats (diastolic). Express these pressures in the following units. Place the systolic in the first entry and the diastolic in the second.

     (i)     120 torr  and 80 torr

     (ii)    0.157 atm and 0.105 atm

    (iii)    0.159 bar and 0.106 bar

    (iv)   15.99 kpa and 10.66 kpa

Explanation:

  We know  

                    1 atm = 760 mmHg = 760 torr

              ⇒  1 mmHg = 0.00131579 atm

             ⇒   1 mmHg = 1 torr

             ⇒   1 mm Hg = 0.00133322 bar

             ⇒   1 mmHg = 133.322 pa = 0.133322 kilo pascal

                Systolic pressure                                         Diastolic pressure

     (i)     120 mmHg = 120 torr                                        80 mmHg = 80 torr

     (ii)      120 mmHg = 120 x 0.00131579 atm                80 mmHg = 0.105 atm

                                  = 0.157 atm

    (iii)      120 mmHg = 120 x 0.00133322 bar                80 mmHg = 0.106 bar

                                  = 0.159 bar

    (iv)      120 mmHg = 120 x 0.133322 kpa                   80 mmHg = 10.66 kpa

                                  = 15.99 kpa

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g