Answer:
4.64E14
Explanation:
First convert 645 nm to m = 6.4500E-7m. The equation for finding v with these values is the speed of light/wavelength. so 2.998E8/6.4500E-7m.
so your v or frequency would equal 4.64E14
Fun fact you know this is visible light because the visible light range is within the E14 range.
Answer:
De la Alex;)(da alex ăla de e din cls cu tn:)
Answer:
A) 4P + 5O₂ → 2P₂O₅
Explanation:
A) 4P + 5O₂ → 2P₂O₅
This equation is balanced. There are four phosphorus and ten oxygen atoms are on both side of equation.
B) 5P + 4O₂ → 2P₄O₅
This equation is not balanced. There are five phosphorus and eight oxygen atoms on left, eight phosphorus ten oxygen on right side of equation.
C) 2P + O₂ → P₂O₅
This equation is not balanced. There are two phosphorus, two oxygen atoms on left and two phosphorus five oxygen on right side of equation.
D) 4P + 2O₂ → 2P₄O₅
This equation is not balanced. There are four phosphorus, four oxygen atoms on left and eight phosphorus ten oxygen on right side of equation.
Answer: 1709.4 Joules
Explanation:
The quantity of Heat Energy (Q) released on cooling a heated substance depends on its Mass (M), specific heat capacity (C) and change in temperature (Φ)
Thus, Q = MCΦ
Since Q = ?
M = 18.5 grams
Recall that the specific heat capacity of copper C = 0.385 J/g.C
Φ = 285°C - 45°C = 240°C
Then, Q = MCΦ
Q = 18.5grams x 0.385 J/g.C x 240°C
Q = 1709.4 Joules
Thus, 1709.4 Joules is released when copper is cooled.