1. A. All the elements in the column have similar chemical properties.
2. Substances on the periodic table cannot be broken down into other substances and are therefore elements.
Reactivity trends of halogen:
1) Melting point and boiling points increased down the
group
2) Colour becomes darker.
E.g. Fluorine (pale yellow)
Chlorine (yellowish-green)
Bromine (reddish-brown)
Iodine (purplish-black)
Astatine (black)
3) The reactivity decreases down the group.
Reactivity:
F > Cl > Br > I > At
pH of 0.40M triethylammonium chloride is 5.90.
<h3>What is pH?</h3>
A solution's acidity may be determined by looking at its pH, which is a measurement of hydrogen ion concentration. Pure water slightly separates into ions with roughly equal amounts of hydrogen and hydroxyl (OH) ions. [H+] is 107 for a neutral solution, or pH = 7.
<h3>Given : </h3>
Concentration of triethylammonium chloride = 0.40M
pH = ?
<h3>Solution: </h3>
(CH3CH2)3NHCl ------> (CH3CH2)3NH⁺ + Cl⁻
(CH3CH2)3NH⁺ will react with water to give H3O⁺ .
(CH3CH2)3N will have a Kb = 5.2 x 10 ^(-4)
Kw = Kb x Ka
=> Ka = Kw / Kb = 10^(-14) / 5.2 x 10 ^(-4)
=> Ka = 1.92 x 10^(-11)
so by the reaction we have ,
Ka = x²/(0.40 - x)
=> x = 1.2393 x 10 ^(-6)
now, pH = -log( [H3O⁺]) = - log ( 1.2393 x 10 ^(-6)) = 5.906
To learn more about pH :
brainly.com/question/15289741
#SPJ4
Answer:
Answer is given below:
Explanation:
<em>Given Data:</em>
mass = 80kg
acceleration = 4 ms
force = 800N
<em>Find out:</em>
friction = ?
<em>Formula</em><em>:</em>
F-friction = weight - f-net
<em>Solution:</em>
weight = (80)(10)
= 800 N
F-net = ma =(80)(4) = 320N
F-friction = weight - F-net
=800 N - 320N
=480N
<em>Answer</em> :
Friction = 480 N