C; The Valence electrons spend more time around the atom of F
The much of the sample that would remain unchanged after 140 seconds is 2.813 g
Explanation
Half life is time taken for the quantity to reduce to half its original value.
if the half life for Scandium is 35 sec, then the number of half life in 140 seconds
=140 sec/ 35 s = 4 half life
Therefore 45 g after first half life = 45 x1/2 =22.5 g
22.5 g after second half life = 22.5 x 1/2 =11.25 g
11.25 g after third half life = 11.25 x 1/2 = 5.625 g
5.625 after fourth half life = 5.625 x 1/2 = 2.813
therefore 2.813 g of Scandium 47 remains unchanged.
Answer:
fe+s is a mixture of iron and sulphur and it can be separated by magnetic separation. But FeS is a compound formed by heating iron and sulphur together.it can't be separated by any method.
Here are some of the differences between a mixture of iron and sulfur, and iron sulfide: the mixture can contain more or less iron, but iron sulfide always contains equal amounts of iron and sulfur. the iron and sulfur atoms are not joined together in the mixture, but they are joined together in iron sulfide.
When the block of iron is placed in water the volume of water that is displaced is 27.0 cm³
<u><em> calculation</em></u>
The volume water that is displaced is equal to volume of block of the iron
volume of block of iron = length x width x height
length= 3 cm
width = 3 cm
height = 3 cm
volume is therefore = 3 cm x 3 cm x 3 cm = 27 cm³ therefore the volume displaced = 27 cm³ since the volume of water displaced is equal to volume of block.
Answer:
You see, plants need energy to grow and grow and grow. They use energy from sunlight to make a simple sugar, glucose. Whenever the plant needs energy, it can chomp a little glucose off of the starch.
without energy it wont get energy/food so it will eventually die
Explanation:
