The table below shows some physical properties of two unknown samples. physical propertiessample mass freezing pointa 1000 ml 0 °cb 1000 ml −95 °cwhat would best support whether the two samples are of the same substance or not? a. the two substances are the same because their intensive property is same. b. the two substances are the same because their extensive property is different. c. the two substances are not the same because their extensive property is same. d. the two substances are not the same because their intensive property is different.

Extensive property is that which depends on the amount of matter in a sample. For example: mass, volume, size  are all extensive properties

Intensive properties are independent of the amount of matter. These include; boiling point, melting point, color and so on.

In the given examples:

Both sample A and B have the same volume (1000 ml) i.e. the same extensive property. However, they have different freezing points i.e. different intensive property.

Ans: D) The two substances are not the same because their intensive property is different.

the grams   of   barium that   are in   2.3 x 10^23   atoms of barium   is   52.4 g (answer c)

    calculation

mass = moles   of ba   x molar   mass of ba

  molar mass of ba from periodic table=   137.3 g/mol

  use the   avogadro's law   constant   to   calculate the moles of barium

  that   is     1 mole =   6.02   x 10^23 atoms

                    ? moles = 2.3 x 10^23   atoms

by cross   multiplication

=(1 mole   x 2.3x 10^23 atoms)   / 6.02   x10^23 atoms)=   0.382   moles

mass   is therefore = 137.3   g/mol x 0.382 mol = 52.4 ( answer c)

explanation:

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.