Hypothesis, experiment, conclusion<span />
Answer:
E = 3.6×10⁻¹⁹ J
Explanation:
Given data:
Wavelength = 550 nm (550 ×10⁻⁹ nm)
Energy of wave = ?
Solution:
Formula:
E = h c/λ
c = 3×10⁸ m/s
h = 6.63×10⁻³⁴ Js
Now we will put the values in formula.
E = 6.63×10⁻³⁴ Js × 3×10⁸ m/s /550 ×10⁻⁹ nm
E = 19.89×10⁻²⁶ J.m /550 ×10⁻⁹ nm
E = 0.036×10⁻¹⁷ J
E = 3.6×10⁻¹⁹ J
Answer:
31
Explanation:
In order for an atom to have a neutral charge, it needs to have the same number of protons and electrons. You can see by the illustration that the atomic number is 31, so this element has 31 protons. Knowing that, we also know that it must have 31 electrons to be neutral.
Answer:
b) It produces electrical current spontaneously.
Explanation:
Cells capable of converting chemical energy to electrical energy and vice versa are termed Electrochemical cells. There are two types of electrochemical cells viz: Galvanic or Voltaic cells and Electrolytic cells. Voltaic cell is an elctrochemical cell capable of generating electrical energy from the chemical reaction occuring in it.
The voltaic cell uses spontaneous reduction-oxidation (redox) reactions to generate ions in a half cell that causes electric currents to flow. An half cell is a part of the galvanic cell where either oxidation or reduction reaction is taking place. Hence, the spontaneous production of electric currents is true about Voltaic/Galvanic cells.
Hey there!
Exothermic reactions release heat, causing its temperature to fall. If the reaction is lessening the temperature of the object while releasing all the heat, then you know that the reaction is indeed exothermic. Hope this helps!