Hey! 1) Convection [Warm water is less dense, so it rises.] 2) Conduction [The metal skewer is heated by the fire, and it is directly touching your hand. The metal skewer transfers heat to your hand through conduction.] 3) Conduction [The rock is directly touching you, so it transfers heat to you through conduction.] 4) Convection [Convection causes weather systems because hot air sinks and cold air sinks] 5) Convection [The hot air rises because it is less dense while the cold air sinks because it is denser.] ~Hope this helped~
Answer:
pKa = 3.675
Explanation:
∴ <em>C</em> X-281 = 0.079 M
∴ pH = 2.40
let X-281 a weak acid ( HA ):
∴ HA ↔ H+ + A-
⇒ Ka = [H+] * [A-] / [HA]
mass balance:
⇒<em> C</em> HA = 0.079 M = [HA] + [A-]
⇒ [HA] = 0.079 - [A-]
charge balance:
⇒ [H+] = [A-] + [OH-]... [OH-] is negligible; it comes from to water
⇒ [H+] = [A-]
∴ pH = - log [H+] = 2.40
⇒ [H+] = 3.981 E-3 M
replacing in Ka:
⇒ Ka = [H+]² / ( 0.079 - [H+] )
⇒ Ka = ( 3.981 E-3 )² / ( 0.079 - 3.981 E-3 )
⇒ Ka = 2.113 E-4
⇒ pKa = - Log ( 2.113 E-4 )
⇒ pKa = 3.675
Mass of this substance = 9.928 g
<h3>Further explanation</h3>
Molarity is a way to express the concentration of the solution
Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution
Where
M = Molarity
n = Number of moles of solute
V = Volume of solution
So to find the number of moles can be expressed as
mol of substance -Lithium nitrite - LiNO₂ :
V = 250 ml = 0.25 L
M = 0.75 M
So mass of this substance - LiNO₂ (MW=52,947 g/mol) :
PH: 4.80617997
pOH: 9.1938200
[H+]: 1.562
[OH-] 6.4E-10
Acid
Answer:
5
Explanation:
Balance the equation in order of C,H,O and then you should be able to find the coefficient
