Answer:
The answers are explained below
Explanation:
a)
Given: concentration of salt/base = 0.031
concentration of acid = 0.050
we have
PH = PK a + log[salt]/[acid] = 1.8 + log(0.031/0.050) = 1.59
b)
we have HSO₃⁻ + OH⁻ ------> SO₃²⁻ + H₂O
Moles i............0.05...................0.01.................0.031.....................0
Moles r...........-0.01.................-0.01................0.01........................0.01
moles f...........0.04....................0....................0.041.....................0.01
c)
we will use the first equation but substituting concentration of base as 0.031 + 10ml = 0.031 + 0.010 = 0.041
Hence, we have
PH = PK a + log[salt]/[acid] = 1.8 + log(0.041/0.050) = 1.71
d)
pOH = -log (0.01/0.510) = 1.71
pH = 14 - 1.71 = 12.29
e)
Because the buffer solution (NaHSO3-Na2SO3) can regulate pH changes. when a buffer is added to water, the first change that occurs is that the water pH becomes constant. Thus, acids or bases (alkali = bases) Additional may not have any effect on the water, as this always will stabilize immediately.
Heat = mass * heat capacity of water * change in temperature
mass = 5.25 g
heat capacity of water = 4.186 joule/gram °C
Change in temperature = 62.8°C - 5.3°C = 57.5 °C
Plug in the values
heat = 5.25 g * 4.186 joule/gram °C * 57.5 °C = 1263.6 J
Rounded to two three significant figures, it is 1260 J of energy needed.
In terms of calories, the heat capacity of water is 1 calorie/gram °C. So do the plugging in all over again.
mass = 5.25 g
heat capacity of water = 1 calorie/gram °C
Change in temperature = 62.8°C - 5.3°C = 57.5 °C
heat = 5.25 g * 1 calorie/gram °C * 57.5 °C = 301.9 calories
Rounded to 3 significant figures, it is 302 calories
Q=SM∆T=4.18*5.25*(62.8-4.3)=1280 J
1280 J * (1 cal/4.18 J) = 307 cal
Answer:
Atoms with high electro negativity
<h3>Answer:</h3>
The reactivity of an alkali metal depends on the metals ability to <u>loose an electron</u>.
<h3>Explanation:</h3>
Alkali metals are elements present in first group of the periodic table. Following are the metals from top to bottom;
Lithium
Sodium
Potassium
Rubidium
Cesium
Francium
These s-block elements are considered the most reactive metals in the periodic table because they have only one electron in their valence shell and readily loose that electron to form an ionic bond with non metal. The general electronic configuration of these metals is as follow,
nS¹
Also, the reactivity of these metals increases from top to bottom in the group as the ionization energy decreases due to increase in shielding effect respectively.
