The precision of a tool can affect the measurement's accuracy. how specific the measurement can get (if it goes to the tenths place, hundredths, etc) can also affect the accuracy.
323.5g - 301.2g = 22.3g is the change in mass.
The concentration refers to the amount of substance that is contained in solution.
<h3>What is the concentration?</h3>
The concentration refers to the amount of substance that is contained in solution. We can be able to obtain the concentration of the raw acid by the use of the relation;
Co = 10pd/M
M = molar mass of the acid
p = percentage of the acid
d = density of the acid
Co = 10 * 36 * 1.18/36.5
Co = 11.6 M
Using the dilution formula;
C1V1 = C2V2
10 * 11.6 = C2 * 1000
C2 = 10 * 11.6/1000
C2 = 0.116 M
Using again;
C1V1 = C2V2
0.116 * 5 = C2 * 20
C2 = 0.116 * 5 /20
C2 = 0.029 M
Learn more about concentration:brainly.com/question/10725862
#SPJ1
Explanation:
The balanced equation of the reaction is given as;
Mg(OH)2 (s) + 2 HBr (aq) → MgBr2 (aq) + 2 H2O (l)
1. How many grams of MgBr2 will be produced from 18.3 grams of HBr?
From the reaction;
2 mol of HBr produces 1 mol of MgBr2
Converting to masses using;
Mass = Number of moles * Molar mass
Molar mass of HBr = 80.91 g/mol
Molar mass of MgBr2 = 184.113 g/mol
This means;
(2 * 80.91 = 161.82g) of HBr produces (1 * 184.113 = 184.113g) MgBr2
18.3g would produce x
161.82 = 184.113
18.3 = x
x = (184.113 * 18.3 ) / 161.82 = 20.8 g
2. How many moles of H2O will be produced from 18.3 grams of HBr?
Converting the mass to mol;
Number of moles = Mass / Molar mass = 18.3 / 80.91 = 0.226 mol
From the reaction;
2 mol of HBr produces 2 mol of H2O
0.226 mol would produce x
2 =2
0.226 = x
x = 0.226 * 2 / 2 = 0.226 mol
3. How many grams of Mg(OH)2 are needed to completely react with 18.3 grams of HBr?
From the reaction;
2 mol of HBr reacts with 1 mol of Mg(OH)2
18.3g of HBr = 0.226 mol
2 = 1
0.226 = x
x = 0.226 * 1 /2
x = 0.113 mol
ΔH=MCΔT
ΔH=100 x 4.2 x 4
ΔH=1680
ΔH per mole = ΔH ÷ moles
ΔH per mole = 1680 ÷ 0.02
<span>ΔH per mole= 84000Jmol
</span>84000 ÷ 1000 = 84KJmol
its exothermic as heat is given out into the solution
