Select the correct answer from A, B, C, D & E for each statement given below:

Which natural law do biogeochemical cycles address?

emmainna [20.7K]

Im not completely sure but It might be Cycling of Matter

4 0

3 years ago

Convert the composition of the following alloy from atom percent to weight percent (a) 44.9 at% of silver, (b) 46.3 at% of gold,

vesna_86 [32]

Answer:

Mass percentage of gold : 33.35%

Mass percentage of silver: 62.80%

Mass percentage of copper : 3.85%

Explanation:

$N=n\times N_A$

Where : N = Number of atoms

n = moles

$N_A=6.022\times 10^{23}$ = Avogadro number

Let the total atoms present in the alloy be 100.

Atom percentage of silver = 44.9%

Atoms of of silver = 44.9% of 100 atoms = 44.9

Atomic weight of silver = 107.87 g/mol

Mass of 44.9 silver atoms = 107.87 g/mol × 44.9 = 4,843.363 g/mol

Atom percentage of gold= 46.3%

Atoms of of gold = 46.3% of 100 atoms = 46.3

Atomic weight of gold = 196.97 g/mol

Mass of 44.9 gold atoms = 196.97 g/mol × 46.3 = 9,119.711 g/mol

Atom percentage of copper = 8.8 %

Atoms of of copper = 8.8% of 100 atoms = 8.8

Atomic weight of copper = 63.55 g/mol

Mass of 44.9 copper atoms = 63.55 g/mol × 8.8 = 559.24 g/mol

Total mass of an alloy :4,843.363 g/mol + 9,119.711 g/mol + 559.24 g/mol

Mass percentage of gold :

$\frac{4,843.363 g/mol}{4,843.363 g/mol + 9,119.711 g/mol + 559.24 g/mol}\times 100=33.35 \%$

Mass percentage of silver:

$\frac{9,119.711 g/mol}{4,843.363 g/mol + 9,119.711 g/mol + 559.24 g/mol}\times 100=62.80\%$

Mass percentage of copper :

$\frac{559.24 g/mol}{4,843.363 g/mol + 9,119.711 g/mol + 559.24 g/mol}\times 100=3.85\%$

7 0

3 years ago

How do you balance this Chemical Equation? <br>C5H12O + O2 = CO2 + H2O

ICE Princess25 [194]

Answer:

The chemical equation by putting, a 2 on C₅H₁₂O, 15 on O₂, 10 on CO₂ , and 12 on H₂O in the equation;

2C₅H₁₂O + 15O₂ → 10CO₂ + 12H₂O

Explanation:

Chemical equations are balanced by putting coefficients on the reactants and products to ensure the total number of atoms on the left side equal to those on the right side.
Balancing chemical equations is done to make chemical equations obey the law of conservation of mass.
According to the law of conservation of mass, the mass of the reactants should always be equal to the mass of products.
This is done by balancing chemical equations to ensure the total number of atoms on the left side is equal to that on the right side.

Therefore, the balanced equation is;

2C₅H₁₂O + 15O₂ → 10CO₂ + 12H₂O

3 0

3 years ago

Relative dating determines the relative age of fossils according to

KiRa [710]

The answer Is C.the layer of rock they're found in

7 0

3 years ago

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Indicate the charge carried by the following atomic particles:

Dovator [93]

Answer:
A. Protons are positive and carry a charge of +1
B. Neutrons are neutral so carry a charge of 0
C. Electrons are negative and carry a charge of -1

5 0

2 years ago

Read 2 more answers