Answer:
The solution is given below
Explanation:
Heat, q= mc∆T
q= 125g x 4.18 J/g∙°C x (21.18x- 24.28) °C
q= -1619.75J
NEGATIVE SIGN INDICATES THAT HEAT IS ABSORBED.
Enthalpy Change, ∆H = 1619.75 7/ 10.5 g
= 154.26 J/g
No. of moles of KBr = Mass of KBr/ Molecular Weight of KBr
=10.5g/119gmol-1
=0.088 mol
∆H= 1619.75 J/ 0.088 mol
= 18.41 kJ/mol
<span>Molds are created to achieve a
specific design of a material. These materials either came from a process of
having a higher or lower temperature. Therefore, the molder must have thermal
resistant properties. Low melting points means that the material to be shaped
came from a cooler process. Wood and metal have higher thermal conductivity and
therefore can easily be cooled. The wax can turn really hard and can be
unbreakable when present in colder materials due to the lipids present in it. Clay
however can become a mold because of its low melting point.</span>
Answer:
FeCl₃ is present in excess.
Explanation:
Given data:
Number of moles of FeCl₃ = 6 mol
Number of moles of oxygen = 3 mol
Excess reactant = ?
Solution:
Chemical equation:
4FeCl₃ + 3O₂ → 2Fe₂O₃ + 6Cl₂
Now we will compare the moles of reactant with product.
FeCl₃ : Fe₂O₃
4 : 2
6 : 2/4×6= 3
FeCl₃ : Cl₂
4 : 6
6 : 6/4×6= 9
O₂ : Fe₂O₃
3 : 2
O₂ : Cl₂
3 : 6
Less number of moles of product are formed by the oxygen thus it will act as limiting reactant while FeCl₃ is present in excess.
Mathematical formula of Ideal Gas Law is PV=nRT
where: P-pressure,
V-volume
n-number of moles; m/MW
T-Temperature
m-mass
d-density ; m/V
MW-Molecular Weight
R- Ideal Gas constant. If the units of P,V,n & T are atm, L, mol & K respectively, the value of R is 0.0821 L x atm / K x mol
Substituting the definitions to the original Gas equation becomes:
d= P x MW / (RxT)
Solution : d= .90atm x 28 g/mol (CO) / 0.0821Lxatm / mol x K x 323 K
d = 25.2 g / 26000 mL
d = .0.00096 g/mL is the density of CO under the new conditions
<span>The ion concentration measure the ability of water to conduct an electric current. </span>