A. Adding a catalyst. A catalyst by definition is a compound that speeds up reaction rates.
Answer:
39.7 %
Explanation:
magnesium + oxygen ⟶ magnesium oxide
10.57 g 6.96 g 17.53 g
According to the <em>Law of Conservation of Mass</em>, the mass of the product must equal the total mass of the reactants.
Mass of MgO = 10.57 + 6.96
Mass of MgO = 17.53 g
The formula for mass percent is
% by mass = Mass of component/Total mass × 100 %
In this case,
% O = mass of O/mass of MgO × 100 %
Mass of O = 6.96 g
Mass of MgO = 17.53 g
% O = 6.96/17.53 × 100
% O = 0.3970 × 100
% O = 39.7 %
Answer:
1.98x10⁻¹² kg
Explanation:
The <em>energy of a photon</em> is given by:
h is Planck's constant, 6.626x10⁻³⁴ J·s
c is the speed of light, 3x10⁸ m/s
and λ is the wavelenght, 671 nm (or 6.71x10⁻⁷m)
- E = 6.626x10⁻³⁴ J·s * 3x10⁸ m/s ÷ 6.71x10⁻⁷m = 2.96x10⁻¹⁹ J
Now we multiply that value by <em>Avogadro's number</em>, to <u>calculate the energy of 1 mol of such protons</u>:
- 1 mol = 6.023x10²³ photons
- 2.96x10⁻¹⁹ J * 6.023x10²³ = 1.78x10⁵ J
Finally we <u>calculate the mass equivalence</u> using the equation:
- m = 1.78x10⁵ J / (3x10⁸ m/s)² = 1.98x10⁻¹² kg
It is make the molecule polar.
