Technically it's grp 1 elements...the answer is ribidium Rb
Answer:
1.7 ppm
Explanation:
Original amount N' = 2.6 ppm
time to testing t = 24 hr
final amount N = 2.1 ppm
Using exponential inhibited decay, we have
N = N'e^(-kt)
Where
N is the new reading
N' is the original reading
t is the decay time
k is the decay constant
Substituting, we have
2.1 = 2.6 x e^(-k x 24)
2.1 = 2.6 x e^(-24k)
0.808 = e^(-24k)
We take the natural log of both sides of the equation
Ln 0.808 = Ln (e^(-24k))
-0.213 = - 24k
K = 0.213/24 = 0.00886
After 48 hrs, the reading of free chlorine will be
N = 2.6 x e^(-0.00886 x 48)
N = 2.6 x e^(-0.425)
N = 2.6 x 0.654
N = 1.7 ppm
<h3>
Answer:</h3>
1379.4 Joules
<h3>
Explanation:</h3>
- The quantity of heat is calculated multiplying the mass of a substance by heat capacity and the change in temperature.
Therefore;
Quantity of heat = Mass × specific heat capacity × Change in temperature
Q = mcΔT
In this case;
The substance dissolved in water gained heat while water lost heat energy.
Thus, Heat gained by the substance = heat lost by water
Heat associated with the water
Mass of water = 75 g
Change in temperature = 4.4°C
Specific heat capacity = 4.18 J/g·⁰C
Heat = mcΔT
= 75 g × 4.18 J/g·⁰C × 4.4 °C
=1379.4 Joules
Explanation:
The starch requires a temperature higher than the room temperature (arround 60 °C) to decompose to form simple sugars. This is because the energy required to break the chemical bonds. Also, it may need the action of some specific enzymes (alpha and beta amilase) to break those bonds.
Answer:
0.74M
Explanation:
Step 1 :
Data obtained from the question.
Initial concentration (C1) = 3M
Initial volume (V2) = 185mL
Final volume (V2) = 750mL
Final concentration (C2) =..?
Step 2:
Determination of the new concentration of the solution.
The new concentration of the solution can be obtained by using the dilution formula as shown below:
C1V1 = C2V2
3 x 185 = C2 x 750
Divide both side by 750
C2 = 3 x 185 / 750
C2 = 0.74M
Therefore, the new concentration of the solution is 0.74M
