Answer:
volume in L = 0.25 L
Explanation:
Given data:
Mass of Cu(NO₃)₂ = 2.43 g
Volume of KI = ?
Solution:
Balanced chemical equation:
2Cu(NO₃)₂ + 4KI → 2CuI + I₂ + 4KNO₃
Moles of Cu(NO₃)₂:
Number of moles = mass/ molar mass
Number of moles = 2.43 g/ 187.56 g/mol
Number of moles = 0.013 mol
Now we will compare the moles of Cu(NO₃)₂ with KI.
Cu(NO₃)₂ : KI
2 : 4
0.013 : 4 × 0.013=0.052 mol
Volume of KI:
<em>Molarity = moles of solute / volume in L</em>
volume in L = moles of solute /Molarity
volume in L = 0.052 mol / 0.209 mol/L
volume in L = 0.25 L
Answer:
Ok:
Explanation:
So, you can use the Henderson-Hasselbalch equation for this:
pH = pKa + log(
) where A- is the conjugate base of the acid. In other words, A- is the deprotonated form and HA is the protonated.
We can solve that
1 = log(
) and so 10 = or 10HA = A-. For every 1 protonated form of adenosine (HA), there are 10 A-. So, the percent in the protonated form will be 1(1+10) or 1/11 which is close to 9 percent.
Answer:
Energy transfers from the metal to the water and calorimeter until they are all at room temperature.
Explanation:
CHECK THE COMPLETE QUESTION BELOW;
A metal sample is heated and placed into the water in a calorimeter at room temperature. Which statement best describes how the calorimeter can be used to determine the specific heat capacity of the metal sample?
Energy transfers to the metal from the water and calorimeter until they are all at room temperature
. Energy transfers from the metal to the water and calorimeter until they are all at room temperature.
Energy transfers to the metal from the water and calorimeter until they all reach a single temperature.
Energy transfers from the metal to the water and calorimeter until they all reach a single temperature.
EXPLANATION;
Using calorimeter to determine the specific heat capacity of the metal sample can be associated to the theory of conservation of energy because heat which is a form of energy is been transfer of heat between the metal to the water and the calorimeter, this process will proceed till single temperature is attained.
The change in the amount of temperature of the water in the calorimeter is measured in order to get the difference in heat change of the calorimeter water.
CHANGE IN HEAT CAN BE CALCULATED USING THE FORMULA.
Q = cmΔT where Q is the change in heat , c is the specific heat capacity and ΔT is the change in temperature
Let's evaluate each choice. For the first choice, this is correct. Hydrosphere consist of all the water's in the Earth's surface. It interacts with the atmosphere through reaeration, so that water cycle continues on. The second option is correct, this is known as the greenhouse effect. The third option is incorrect, because the opposite is true, which makes the fourth option correct. The fifth option is incorrect because the atmosphere has nothing to do with the Earth's crust. <em>So, the answers are: A, B, and D.</em>
Answer:
1.244x10^23 molecules
Explanation:
From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules.
This means that 1mole of SiO2 contains 6.02x10^23 molecules
1mole of SiO2 = 28 + (2x16) =28 +32 = 60g
If 1 mole(i.e 60) of SiO2 contains 6.02x10^23 molecules,
Therefore, 12.40g of SiO2 will contain = (12.40 x 6.02x10^23) / 60 = 1.244x10^23 molecules
