12.88 x 1000 = 12,880 g
4.77 x 1000 = 4770 cm³
D = mass / volume
D = 12,880 / 4770
D = 2.70 g/cm³
hope this helps!
Answer:
It is
D- <u><em>DEFINE</em></u> the problem
R-<em><u>RESEARCH</u></em> on the problem
H- Carry out a <u><em>HYPOTHESIS</em></u>
E- carry out an <em><u>EXPERIMENT</u></em>.
R-Analyse the <u><em>RESULT</em></u>
C-summarise the <u><em>CONCLUSION</em></u>.
Explanation:
Hope it helps.
Answer:
Sexual and Asexual Reproduction
Explanation:
LOL
Answer:
42.3%
Explanation:
By the reaction given the stoichiometry between MnO₄⁻ and Fe⁺² is 1 mol of MnO₄⁻ to 5 moles of Fe⁺². When KMnO₄ dissolves, it forms the same amount of K⁺ and MnO₄⁻ (1:1:1), so the number of moles of MnO₄⁻ used is:
n = Volume*concentration
n = 0.0216 L * 0.102 mol/L
n = 2.20x10⁻³ mol
1 mol of MnO₄⁻ -------------------- 5 moles of Fe⁺
2.20x10⁻³ mol ---------------------- x
By a simple direct three rule
x = 0.011 mole
The molar mass of iron is 55.8 g/mol. The mass is the molar mass multiplied by the number of moles, thus:
m = 55.8*0.011
m = 0.614 g
Then, the percent of iron in the ore is:
(mass of iron/ mass of ore) *100%
(0.614/1.45)*100%
42.3%
Answer : The atomic mass of chlorine is, 36.723 amu
Explanation :
Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.
Formula used to calculate average atomic mass follows:

As we are given that,
Mass of 35-Cl isotope = 35 amu
Percentage abundance of 35-Cl isotope = 13.85 %
Fractional abundance of 35-Cl isotope = 0.1385
Mass of 37-Cl isotope = 37 amu
Percentage abundance of 37-Cl isotope = 86.15 %
Fractional abundance of 37-Cl isotope = 0.8615
Now put all the given values in above formula, we get:
![\text{Average atomic mass }=[(35\times 0.1385)+(37\times 0.8615)]](https://tex.z-dn.net/?f=%5Ctext%7BAverage%20atomic%20mass%20%7D%3D%5B%2835%5Ctimes%200.1385%29%2B%2837%5Ctimes%200.8615%29%5D)

Therefore, the atomic mass of chlorine is, 36.723 amu