Answer:
[H3O+] = 1.0*10^-12 M
[OH-] = 0.01 M
Explanation:
We can use the following equation to find the hydronium ion concentration. Plug in the pH and solve for H3O+.
pH = -log[H3O+]
<u>[H3O+] = 1.0*10^-12 M</u>
Now, to find the hydroxide ion concentration we will use the two following equations.
14 = pH + pOH
pOH = -log[OH-]
14 = 12 + pOH
pOH = 2
2 = -log[OH-]
<u>[OH-] = 0.01 M</u>
multiply the number of each atom with its molecular mass. (see the periodic table)
5*12 + 12*1 = 72 gram per mole.
Or more accurately: 5*12.01078 + 12*1.007947 = 72.149264 g/mole
The correct option is C.
When glucose is stirred into water to form a solution, then glucose is the SOLUTE and water is the SOLVENT. A solute refers to a substance that is dissolved in a solvent. For instance, salt is the solute that is dissolved in salt solution. A solvent on the other hand refers to the liquid into which the solute was dissolved. For instance, in the case of salt solution, water is the solvent, because it is used to dissolve the salt.
Answer:
-1190.24 kJ
Explanation:
The enthalpy change in a chemical reaction that produces or consumes gases is given by the expression:
ΔH = ΔU + Δngas RT
where Δn gas is the change of moles of gas, R is the gas constant,and T is temperature.
Now from the given balanced chemical reaction, the change in number of mol gas is equal to:
Δn gas = mole gas products - mole gas reactants = 2 - 5/2 = -1/2 mol
Sionce we know ΔU and the temperature (298 K), we are in position to calculate the change in enthalpy.
ΔH = -1189 x 10³ J + (-0.5 mol ) 8.314 J/Kmol x 298 K
ΔH = -1.190 x 10⁶ J = -1.190 x 10⁶ J x 1 kJ/1000 J = -1.190 x 10³ J
Answer:
0.062J
Explanation:
Given parameters:
Height of raising the spoon = 21cm
Mass of spoon = 30g
Unknown:
Gravitational potential energy = ?
Solution:
The gravitational potential energy of a body is the energy by virtue of the position of a such a body in space.
It is given as:
G. P. E = mgh
where m is the mass
g is the acceleration due to gravity
h is the height
Convert the parameters to appropriate units.
21cm to m gives 0.21m
30g to kg gives 0.03kg
G.P.E = 0.03 x 9.8 x 0.21 = 0.062J
