Answer:
Endothermic
Explanation:
This would be an endothermic reaction, due to the fact that the water would be signifigantly warmer then the ice cube, which causes it to melt.
Answer:
absorbs heat, which makes it endothermic.
Explanation:
Basically melting ice is it in windows or Mac reaction makes the ice absorbs heat energy which causes a change to occur
Molar mass of the weak base = 82.0343g/mole.
Note: pKa = -logKa
pKb = -logKb
pH + pOH = 14
[H+ ] [OH- ] = 10^-14
Answer:
11.39
Explanation:
Given that:
Given that:
Mass = 1.805 g
Molar mass = 82.0343 g/mol
The formula for the calculation of moles is shown below:
Thus,
Given Volume = 55 mL = 0.055 L ( 1 mL = 0.001 L)
Concentration = 0.4 M
Consider the ICE take for the dissociation of the base as:
B + H₂O ⇄ BH⁺ + OH⁻
At t=0 0.4 - -
At t =equilibrium (0.4-x) x x
The expression for dissociation constant is:
x is very small, so (0.4 - x) ≅ 0.4
Solving for x, we get:
x = 2.4606×10⁻³ M
pOH = -log[OH⁻] = -log(2.4606×10⁻³) = 2.61
pH = 14 - pOH = 14 - 2.61 = 11.39
Answer:
C) plasma
Explanation:
Plasma is the state where electrons are stripped allow these gases to conduct electricity.
In codominance, both allels are expressed in the offspring; In incomplete dominance, only one allele is expressed in the offspring.
In codominance, both alleles are expressed in the offspring; in incomplete dominance, the offspring demonstrate an intermediate form of the alleles from the parents.
In codominance, the offspring demonstrate an intermediate form of the alleles from the parents; in incomplete dominance, both alleles are expressed in the offspring.
Answer:
C Because im in 3rd grade and just did the test
Explanation:
im smart im in third grade but your doing this in college
Answer:
answer is c: In codominance, both alleles are expressed in the offspring; in incomplete dominance, the offspring demonstrate an intermediate form of the alleles from the parents.
Explanation:
b. 72.8 g c2h6o in 2.34 l of solution
c. 12.87 mg ki in 112.4 ml of solution
The molarities of the given solutions: (a). 0.38 mol of LiNO₃ in 6.14 L of solution has a molarity of 0.062 M. (b). 72.8 g of C₂H₆O in 2.34 L of solution has a molarity of 0.675 M. (c). 12.87 mg of KI in 112.4 mL of solution has a molarity of 0.000688 M.
To calculate the molarity (M) of a solution, you can use the formula:
Molarity (M) = moles of solute / volume of solution (in liters)
a. 0.38 moles of LiNO₃ in 6.14 L of solution:
Molarity (M) = 0.38 moles / 6.14 L = 0.062 M
b. 72.8 grams of C₂H₆O (ethyl alcohol) in 2.34 L of solution:
First, you need to convert grams to moles using the molar mass of C₂H₆O.
Molar mass of C₂H₆O = 2(12.01 g/mol) + 6(1.01 g/mol) + 1(16.00 g/mol) = 46.08 g/mol
Now, calculate moles of C₂H₆O:
moles = 72.8 g / 46.08 g/mol = 1.58 moles
Molarity (M) = 1.58 moles / 2.34 L = 0.675 M
c. 12.87 mg of KI in 112.4 mL of solution:
First, convert milligrams to grams (1 g = 1000 mg):
12.87 mg = 12.87 g (since 12.87 mg / 1000 = 0.01287 g)
Now, convert mL to liters (1 L = 1000 mL):
112.4 mL = 0.1124 L
Calculate moles of KI:
Molar mass of KI = 39.10 g/mol (for K) + 126.90 g/mol (for I) = 166.00 g/mol
moles = 0.01287 g / 166.00 g/mol = 7.75 × 10⁻⁵ moles
Molarity (M) = (7.75 × 10⁻⁵ moles) / 0.1124 L = 0.000688 M
So, the molarities of the solutions are as follows:
a. 0.062 M
b. 0.675 M
c. 0.000688 M
To know more about moles:
#SPJ3
Answer:
0.294 M
Explanation:
The computation of the final molarity of acetate anion is shown below:-
Lead acetate = Pb(OAc)2
Lead acetate involves two acetate ion.
14.3 gm lead acetate = Mass ÷ Molar mass
= 14.3 g ÷ 325.29 g/mol
= 0.044 mole
Volume of solution = 300 ml.
then
Molarity of lead is
= 0.044 × 1,000 ÷ 300
= 0.147 M
Therefore the molarity of acetate anion is
= 2 × 0.147
= 0.294 M
To calculate the final molarity of acetate anion in the solution, consider the dissociation of lead(II) acetate and the presence of ammonium sulfate. When ammonium sulfate is added, it reacts with the lead(II) cations, leaving only the acetate anions in the solution. The final concentration of acetate anions is therefore the same as the initial concentration.
To calculate the final molarity of acetate anion in the solution, we need to consider the dissociation of lead(II) acetate and the presence of ammonium sulfate. Lead(II) acetate will dissociate into lead(II) cations (Pb2+) and acetate anions (CH3COO-) in solution. However, when ammonium sulfate is added, the sulfate anions (SO42-) react with the lead(II) cations, forming lead(II) sulfate and removing them from solution. This leaves us with only the acetate anions.
First, calculate the concentration of the acetate anions in the lead(II) acetate solution. Then subtract the concentration of the acetate anions that reacted with the lead(II) cations to form lead(II) sulfate. This will give us the final concentration of acetate anions in the solution.
Let's assume we have an initial concentration of lead(II) acetate of X M. The dissociation of lead(II) acetate can be represented as:
Pb(CH3COO)2(s) ⇌ Pb2+(aq) + 2CH3COO-(aq)
Since we assume the volume of the solution doesn't change when the lead(II) acetate is dissolved, the initial concentration of acetate anions is also X M.
When ammonium sulfate is added, it reacts with the lead(II) cations according to the reaction:
Pb2+(aq) + SO4^2-(aq) ⇌ PbSO4(s)
Since the concentration of lead(II) sulfate is negligible, we can assume that all the lead(II) cations react with the sulfate anions. This removes the lead(II) cations from solution, leaving us with only the acetate anions.
Therefore, the final concentration of acetate anions is still X M.
#SPJ3
Answer: a) : negative
b) : positive
c) : positive.
d) : negative
e) : positive.
f) : positive.
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an ordered arrangement to a disordered arrangement, the entropy is said to decrease and vice versa.
is positive when randomness increases and
is negative when randomness decreases.
a)
As ions are moving to solid form , randomness decreases and thus sign of is negative.
b)
As solid is changing to gas, randomness increases and thus sign of is positive.
c)
As 2 moles of reactants are converted to 4 moles of products , randomness increases and thus sign of is positive.
d)
As gas is changing to solid, randomness decreases and thus sign of is negative.
e)
As 7 moles of reactants are converted to 8 moles of products , randomness increases and thus sign of is positive.
f)
As solid is changing to gas, randomness increases and thus sign of is positive.