It required a fixed finite amount these zones are known as energy levels
Answer:
181.82 g/cm3
Explanation:
density is mass / volume so it is 500 / 2.75=181.82 g/cm3
Answer:
C) non renewable resources
Explanation:
These are resources such as oil that are formed over a long period of time but are consumed very quickly.
Let's start to understand this question by a simple combustion reaction involving oxidation of Ethane in the presence of Oxygen. When Ethane is burned in the presence of Oxygen it produces Carbon Dioxide and Water respectively. Therefore, the equation is as,
C₂H₆ + O₂ → CO₂ + H₂O
Above reaction shows the reaction and the equation is unbalanced. Balancing chemical equation is important because according to law of conservation of mass, mass can neither be created nor destroyed. Hence, we should balance the number of elements on both side.
LHS RHS
Carbon Atoms 2 1
Hydrogen Atoms 6 2
Oxygen Atoms 2 3
It means this equation is not obeying the law. Now, how to balance? One way is as follow,
C₂H₆ + O₃ → C₂O₂ + H₆O
LHS RHS
Carbon Atoms 2 2
Hydrogen Atoms 6 6
Oxygen Atoms 3 3
We have balanced the equation by changing the subscripts. But, we have messed up the chemical composition of compounds and molecules like Oxygen is converted into Ozone.
Therefore, we will change the coefficients (moles) to balance the equation as,
C₂H₆ + 7/2 O₂ → 2 CO₂ + 3 H₂O
LHS RHS
Carbon Atoms 2 2
Hydrogen Atoms 6 6
Oxygen Atoms 7 7
Now, by changing the coefficients we have balanced the equation without disturbing the chemical composition of compounds and molecules.
Answer:
a) 1.866 × 10 ⁻¹⁹ J b) 3.685 × 10⁻¹⁹ J
Explanation:
the constants involved are
h ( Planck constant) = 6.626 × 10⁻³⁴ m² kg/s
Me of electron = 9.109 × 10 ⁻³¹ kg
speed of light = 3.0 × 10 ⁸ m/s
a) the Ek ( kinetic energy of the dislodged electron) = 0.5 mu²
Ek = 0.5 × 9.109 × 10⁻³¹ × ( 6.40 × 10⁵ )² = 1.866 × 10 ⁻¹⁹ J
b) Φ ( minimum energy needed to dislodge the electron ) can be calculated by this formula
hv = Φ + Ek
where Ek = 1.866 × 10 ⁻¹⁹ J
v ( threshold frequency ) = c / λ where c is the speed of light and λ is the wavelength of light = 358.1 nm = 3.581 × 10⁻⁷ m
v = ( 3.0 × 10 ⁸ m/s ) / (3.581 × 10⁻⁷ m ) = 8.378 × 10¹⁴ s⁻¹
hv = 6.626 × 10⁻³⁴ m² kg/s × 8.378 × 10¹⁴ s⁻¹ = 5.551 × 10⁻¹⁹ J
5.551 × 10⁻¹⁹ J = 1.866 × 10 ⁻¹⁹ J + Φ
Φ = 5.551 × 10⁻¹⁹ J - 1.866 × 10 ⁻¹⁹ J = 3.685 × 10⁻¹⁹ J
