Answer:
1.21 g of Tris
Explanation:
Our solution if made of a solute named Tris
Molecular weight of Tris is 121 g/mol
[Tris] = 100 mM
This is the concentration of solution:
(100 mmoles of Tris in 1 mL of solution) . 1000
Notice that mM = M . 1000 We convert from mM to M
100 mM . 1 M / 1000 mM = 0.1 M
M = molarity (moles of solute in 1 L of solution, or mmoles of solute in 1 mL of solution). Let's determine the mmoles of Tris
0.1 M = mmoles of Tris / 100 mL
mmoles of Tris = 100 mL . 0.1 M → 10 mmoles
We convert mmoles to moles → 10 mmol . 1mol / 1000mmoles = 0.010 mol
And now we determine the mass of solute, by molecular weight
0.010 mol . 121 g /mol = 1.21 g
The answer would be 5.5g because you have to subtract 8.2 minus 2.7 and you get 5.5g so basically the answer is C.
Answer: The ratio of atoms in calcium bicarbonate ; Ca : H : C : O = 1:2:2:6.
The ratio of atoms in lithium sulfide; Li : S = 2 : 1
Explanation:
In calcium bicarbonate:
In a molecular formula of calcium carbonate there are:
Number of Calcium atoms = 1
Number of Hydrogen atom = 1 × 2 = 2
Number of Carbon atoms = 1 × 2 = 2
Number of Oxygen atoms = 3 × 2 = 6
So, Ca : H : C : O = 1 : 2 : 2 : 6
In lithium sulfide :
In a molecular formula of lithium sulfide there are:
Number of Lithium atoms = 1 × 2 = 2
Number of Sulfur atoms = 1
So, the Li : S = 2 : 1