An aeroplane accelerates from rest at a rate
of 25m/s² for 3 s .calculate final velocity

The final speed is 75 m/s

Explanation:

Constant Acceleration Motion

It's a type of motion in which the velocity of an object changes uniformly in time.

Being a the constant acceleration, vo the initial speed, vf the final speed, and t the time, the following relation applies:

The airplane comes from rest (vo=0) accelerating at a=25 m/s^2 for t=3 s.

The final speed is:

The final speed is 75 m/s

  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

statement #3 on andre"s list is false.