Atomic mass is the answer!!
Explanation: An elements atomic number won’t be able to change
Answer:
The concentration the student should write down in her lab is 2.2 mol/L
Explanation:
Atomic mass of the elements are:
Na: 22.989 u
S: 32.065 u
O: 15.999 u
Molar mass of sodium thiosulfate, Na2S2O3 = (2*22.989 + 2*32.065 + 3*15.999) g/mol = 158.105 g/mol.
Mass of Na2S2O3 taken = (19.440 - 2.2) g = 17.240 g.
For mole(s) of Na2S2O3 = (mass taken)/(molar mass)
= (17.240 g)/(158.105 g/mol) = 0.1090 mole.
Volume of the solution = 50.29 mL = (50.29 mL)*(1 L)/(1000 mL)
= 0.05029 L.
To find the molar concentration of the sodium thiosulfate solution prepared we use the formula:
= (moles of sodium thiosulfate)/(volume of solution in L)
= (0.1090 mole)/(0.05029 L)
= 2.1674 mol/L
Molar mass H₂O = 18.0 g/mol
number of moles :
1.0 / 18.0 => 0.055 moles
1 mole -------------- 6.02 x 10²³ molecules
0.055 moles -------- ? molecules
molecules = 0.055 x ( 6.02 x 10²³) / 1
molecules = 3.311x10²² / 1
= 3.311 x 10²² molecules
hope this helps!
Explanation:
Given parameters:
Density of silver = 10.5g/cm³
Volume of silver given = 4mL
Unknown:
Mass of silver = ?
Solution:
Density of a substance can be expressed as its mass per unit volume
Density = 
we need to convert our volume to cm³ from mL;
1cm³ = 1mL
So 4mL = 4cm³
input the values in;
Mass = density x volume = 10.5 x 4 = 42g
learn more:
Density brainly.com/question/8441651
#learnwithBrainly
1. Solar nebula 2. The sun 3. Planetesimals 4. Inner planets, 5. Outer planets.
I believe that’s it
