295. A river is flowing at the rate of 8 km/h. A swimmer swims across the river with a velocity of 10 km/h
w. r.t. water. The resultant velocity of the man will
be in (km/h):-

18km/h

Explanation:

w - water

s - Swimmer

E- Earth

V (w,E) = 8 km/h

V (s,w) = 10 km/h

V (s,E) = ?

V ( s,E) = V (s,w) + V (w,E)

= 10 + 8

= 18 km/h

ammonium chloride & tallow

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂