A student lifts a 2 kg book from the floor to a desk that is 0.5 meters high. How much work does the student do?

W = 9.8 J

Explanation:

Given that,

Mass of the book, m = 2kg

A student lifts it from the floor to a desk that is 0.5 meters high.

We need to find work done by the student. The work done in lifting the book is given by :

W = mgh

Put all the values,

W = 2 kg × 9.8 m/s² × 0.5 m

W = 9.8 J

So, the required work done is 9.8 J.

answer: what are you talking about?

explanation:

  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