Superman twirls a 0.1 kg hammer tied to the end of a 0.6 m rope with negligible mass
horizontally about his head. the hammer makes 3 revolutions every second. the
tension (newtons) in the rope is approximately

Explanation:

Let be the time period of hammer.

Let be the length of the rope.

Let be the speed of hammer.

Given,

Since speed of hammer is the ratio of distance travelled in one cycle and frequency,

Let be the tension in rope.

Since the tension in the rope is balancing the centripetal force,

  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