Answer:
474 nm or 4.74 x 10^2 nm
Explanation:
c = λv
c (speed of light) = 2.998 x 10^8 m/s
λ = ?
v = 6.32 × 1014 Hz = 6.32 × 1014 1/s
2.998 x 10^8 m/s = (λ)(6.32 × 10^14 1/s)
λ = (2.998 x 10^8 m/s) / (6.32 × 10^14 1/s)
λ = 4.74 x 10^-7 m
λ = 4.74 x 10^-7 m x (1 x 10^9 nm/1 m) = 474 nm
Answer: 65.38g of Ca(OH)2 is needed
Explanation:
From The equation of reaction
2 HCl + Ca ( OH ) 2 ⟶ CaCl 2 + 2 H 2 O
NB: Molar mass of HCl= 1+35.5=36.5
Ca(OH)2= 74
From The stoichiometric equation
2mol of HCl(36.5×2=73) require 1mol of Ca(OH)2 (74g)
Hence 64.5g of HCl will require 64.5×74/73= 65.38g of Ca(OH)2
ACIDIC BEHAVIOR OF SOLUTION
Answer:
2
Explanation:
There are some basic laws that guide the combination of elements chemically. These are the law of conservation of mass, law of definite proportion, law of multiple proportion and the law of reciprocal proportion.
For this question, the useful law to use is the law of definite proportion. Here, it is stated that no matter the method of preparation or source of preparation, the elements of a chemical compound are always present in a fixed ratio.
What this means that at any point in time, the compound titanium dioxide contains one atom of titanium and two atoms of oxygen. This means that both atoms are present at all times in a proportion of 1 to 2 .
pH=4.625
The classification of this sample of saliva : acid
<h3>Further explanation</h3>
The water equilibrium constant (Kw) is the product of concentration
the ions:
Kw = [H₃O⁺] [OH⁻]
Kw value at 25° C = 10⁻¹⁴
It is known [OH-] = 4.22 x 10⁻¹⁰ M
then the concentration of H₃O⁺:
![\tt 10^{-14}=4.22\times 10^{-10}\times [H_3O^+]\\\\(H_3O^+]=\dfrac{10^{-14}}{4.22\times 10^{-10}}=2.37\times 10^{-5}](https://tex.z-dn.net/?f=%5Ctt%2010%5E%7B-14%7D%3D4.22%5Ctimes%2010%5E%7B-10%7D%5Ctimes%20%5BH_3O%5E%2B%5D%5C%5C%5C%5C%28H_3O%5E%2B%5D%3D%5Cdfrac%7B10%5E%7B-14%7D%7D%7B4.22%5Ctimes%2010%5E%7B-10%7D%7D%3D2.37%5Ctimes%2010%5E%7B-5%7D)
pH=-log[H₃O⁺]
Saliva⇒acid(pH<7)
