The Arrhenius definition of acid-base reactions, which was devised by Svante Arrhenius, is a development of the hydrogen theory of acids. ... An Arrhenius base is a substance that dissociates in water to form hydroxide (OH -) ions. In other words, a base increases the concentration of OH - ions in an aqueous solution.
Answer:
2Cr³⁺(aq) + 3S²⁻(aq) ----> Cr₂S₃(s)
Explanation:
When aqueous solutions of chromium(III) chloride and ammonium sulfide are mixed together, chromium (III) chloride and ammonium sulfide undergoes a double displacement reaction to produce chromium (iii) sulphide as a precipitate and ammonium chloride which remains in solution.
The general equation of the reaction is given below:
2CrCl₃(aq) + 3(NH₄)₂S(aq) ----> Cr₂S₃(s) + 6NH₄Cl(aq)
The net equation of the reaction is given below:
2Cr³⁺(aq) + 3S²⁻(aq) ----> Cr₂S₃(s)
Answer:
the stronger light 5.5 m apart from the total illumination
Explanation:
From the problem's statement , the following equation can be deducted:
I= k/r²
where I = intensity of illumination , r= distance between the point and the light source , k = constant of proportionality
denoting 1 as the stronger light and 2 as the weaker light
I₁= k/r₁²
I₂= k/r₂²
dividing both equations
I₂/I₁ = r₁²/r₂²=(r₁/r₂)²
solving for r₁
r₁ = r₂ * √(I₂/I₁)
since we are on the line between the two light sources , the distance from the light source to the weaker light is he distance from the light source to the stronger light + distance between the lights . Thus
r₂ = r₁ + d
then
r₁ = (r₁ + d)* √(I₂/I₁)
r₁ = r₁*√(I₂/I₁) + d*√(I₂/I₁)
r₁*(1-√(I₂/I₁)) = d*√(I₂/I₁)
r₁ = d*√(I₂/I₁)/(1-√(I₂/I₁)) =
r₁ = d/[√(I₁/I₂)-1)]
since the stronger light is 9 times more intense than the weaker
I₁= 9*I₂ → I₁/I₂ = 9 →√(I₁/I₂)= 3
then since d=11 m
r₁ = d/[√(I₁/I₂)-1)] = 11 m / (3-1) = 5.5 m
r₁ = 5.5 m
therefore the stronger light 5.5 m apart from the total illumination
Most of the positively charged particles bounced back at a range of angles as they collided with the atoms in the foil; only a few passed straight through the foil. Therefore, scientists discovered<span> that every atom contains a nucleus where its positive charge and most of its mass are concentrated.</span>
Answer:
b) U235 & U238
Explanation:
Isotopes are the variants of a element which differ in the number of neutrons , and in the nucleon number consequently . All isotopes of the element have same number of the protons but different numbers of the neutrons.
(a) Isotopes are the properties of an element. Hence, not isotopes.
(b) Uranium is the element which exists in mass number 235 and 238 and they are the isotopes of the uranium element. Hence, they are isotopes.
(c) They represent same specie. Hence, not isotopes.
(d) Isotopes are the properties of an element. Hence, not isotopes.
