Answers:
<u>Option B. 4.</u>
Explanation:
The visible spectrum of light emitted by a sample of active or excited hydrogen atoms splits into four wavelengths that are basically four distinct levels of energy in the visible region of the spectrum. There four different wavelengths are 410 nm, 434 nm, 486 nm, and 656 nm. These show for colors according to the spectrum and wavelength violet, blue, green, and red, where 656 nm wavelength is most intense on the spectrum.
M=mol/liter
We know that we have 150ml=.15 L and .1 mol of HCl
Rearranging the molarity equation, we get
mol=M*l
mol=(.15)(.1)
=.015 mol
Answer:
- <em>Alkali metals react with water to produce </em><u>hydroxide and hydrogen gas</u><u>.</u>
Explanation:
That is a chemical property of <em>alkali metals</em>: they are highly reactive and <em>react </em>vigorously <em>with water</em> to produce the correspondant hydroxide and hydrogen gas.
These are some of those reactions:
- 2Li (s) + 2H₂O (l) → 2LiOH (aq) + H₂(g) ↑
- 2Na (s) + 2H₂O (l) → 2NaOH (aq) + H₂(g) ↑
- 2K (s) + 2H₂O (l) → 2KOH (aq) + H₂(g) ↑
The alkali metals are the elements of group 1 of the periodic table: Li, Na, K, Rb, Cs, and Fr. They have one valence electron which may lose easily to form an ion with charge +1.