Answer:
the answer is carrying oxygenated blood and nutrients to cells
The atomic radius increases as you go down a group.
<span>Concentration of a chemical in a solution refers to how many of the chemical's molecules are sitting in a small volume of the solution. Concentration could be measured in molecules per liter, although molecules are so small compared to a liter that we usually use different units (just like we wouldn't want to measure the distance between the earth and the sun in inches). A gradient is a measurement of how much something changes as you move from one region to another. So a concentration gradient is a measurement of how the concentration of something changes from one place to another.
If this doesn't help here's a Khan Academy video </span><span>https://www.khanacademy.org/...and.../concentration-gradients</span>
<u>Answer: </u>The mass of water produced is 44.28 g
<u>Explanation:</u>
We are given:
Volume of oxygen gas = 27.50 L
At STP conditions:
22.4 L of volume is occupied by 1 mole of a substance
27.50 L of oxygen gas will be occupied by = 
The chemical equation for the formation of water follows:
By the stoichiometry of the reaction:
If 1 mole of oxygen gas produces 2 moles of water
So, 1.23 moles of oxygen gas will produce = 
of water
The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:
......(1)
Molar mass of water = 18 g/mol
Plugging values in equation 1:
Hence, the mass of water produced is 44.28 g
Answer:
At the end of second half life 12.5 g will left
Explanation:
Given data:
Total Mass = 50 g
Half lives = 2
Mass remain at the end = ?
Solution:
At time zero = 50 g
At 1st half life = 50 g /2 = 25 g
At second half life = 25 g/2 = 12.5 g
So at the end of second half life 12.5 g will left.
