Answer:
In the calorimeter, water is the <u>exothermic</u>. The salt LiCI, which will dissolve, is the <u>endothermic</u>. The final temperature of the water after the dissolution of LiCI was <u>lower</u> than the initial temperature, meaning the process is <u>exothermic</u>. In the microscopic view of the disspolution of LiCI, water molecules were seen to move <u>slowly</u> as they <u>gained </u>energy.
Explanation:
Exothermic is a process in which heat is released during the process. Endothermic reactions absorbs heat from surrounding during a chemical process. The dissolution of salt into water is an exothermic reaction. During this process heat is release and water molecules are broken down which are surrounded by salt ions.
Answer:
Explanation:
Hello,
In this case, given that the mass of the product is 0.534 g, we can infer that the percent composition of tin is:
Therefore, the percent composition of oxygen is 6.4% for a 100% in total. Thus, with such percents we compute the moles of each element in the oxide:
In such a way, for finding the smallest whole number we divide the moles of both tin and oxygen by the moles of oxygen as the smallest moles:
Therefore, the empirical formula is:
Best regards.
We are given that the balanced chemical reaction is:
cacl2⋅2h2o(aq) +
k2c2o4⋅h2o(aq) --->
cac2o4⋅h2o(s) +
2kcl(aq) + 2h2o(l)
We known that
the product was oven dried, therefore the mass of 0.333 g pertains only to that
of the substance cac2o4⋅h2o(s). So what we will do first is to convert this
into moles by dividing the mass with the molar mass. The molar mass of cac2o4⋅h2o(s) is
molar mass of cac2o4 plus the
molar mass of h2o.
molar mass cac2o4⋅h2o(s) = 128.10
+ 18 = 146.10 g /mole
moles cac2o4⋅h2o(s) =
0.333 / 146.10 = 2.28 x 10^-3 moles
Looking at
the balanced chemical reaction, the ratio of cac2o4⋅h2o(s) and k2c2o4⋅h2o(aq) is
1:1, therefore:
moles k2c2o4⋅h2o(aq) = 2.28
x 10^-3 moles
Converting
this to mass:
mass k2c2o4⋅h2o(aq) = 2.28
x 10^-3 moles (184.24 g /mol) = 0.419931006 g
Therefore:
The mass of k2c2o4⋅<span>h2o(aq) in
the salt mixture is about 0.420 g</span>
The only compound that contains covalent bonds would be A. BCl4-.
Answer:
The partial pressure of NO2 = 0.152 atm
Explanation:
Step 1: Data given
Pressure NO2 = 0.500 atm
Total pressure at equilibrium = 0.674 atm
Step 2: The balanced equation
2NO2(g) → 2NO(g) + O2(g)
Step 3: The initial pressure
pNO2 = 0.500 atm
pNO = 0 atm
p O2 = 0 atm
Step 4: Calculate pressure at the equilibrium
For 2 moles NO2 we'll have 2 moles NO and 1 mol O2
pNO2 = 0.500 - 2x atm
pNO =2x atm
pO2 = xatm
The total pressure = p(total) = p(NO2) + p(NO) + p(O2)
p(total) = (0.500 - 2x) + 2x + x= 0.674 atm
0.500 + x = 0.674 atm
x = 0.174 atm
This means the partial pressure of NO2 = 0.500 - 2*0.174 = 0.152 atm
