Which is a characteristic of the part of the atom marked "A"?
It contains most of the mass.
It is negatively charged.
It is mostly empty space.
It is composed of electrons.

Order can include highly organized structures such as cells, tissues, organs, and organ systems.

Interaction with the environment is shown by response to stimuli.

The ability to reproduce, grow and develop are defining features of life.

The concepts of biological regulation and maintenance of homeostasis are key to survival and define major properties of life.

Organisms use energy to maintain their metabolic processes.

Populations of organisms evolve to produce individuals that are adapted to their specific environment.

  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

measuring things 1 litre of water