Answer:
Elaina's scientific investigation is missing controlled variables.
Explanation:
A good scientific investigation should vary only the factor that is studied (the speed of the music. All other factors should be kept constant.
She hasn’t controlled for <em>volume</em>. The volume of the music may affect the rate at which the listener’s heart rate will increase. She should have measured each person’s pulse after the same period of listening.
She hasn’t controlled for <em>age</em>. A grandmother may respond to loud music differently from a teenager. All her subjects should be about the same age.
She hasn’t controlled for <em>wakefulness</em>. A person may respond to music differently when awake than when asleep.
Answer:
20L
Explanation:
The following data were obtained from the question:
Initial volume (V1) = 10L
Initial Temperature (T1) = stp = 273K
Final temperature (T2) = 546K
Final volume (V2) =..?
The new volume of the gas can be obtained by using the Charles' law equation as shown below:
V1/T1 = V2/T2
10/273 = V2/546
Cross multiply to express in linear form
273 x V2 = 10 x 546
Divide both side by 273
V2 = (10 x 546) / 273
V2 = 20L
Therefore, the new volume of the gas is 20L.
Answer:
Use E = h*c / lambda, where h is Planck's constant, c is the speed of light, and lambda is the wavelength.
E = (6.626 * 10^-34 J*s x 3.00 * 10^8 m/s) / (1*10^-6 m) = 1.99 * 10^-19 J
Explanation:
Answer:
3
Explanation:
You have to mutiply the silver reaction by 3 in order to substract the electrons
When we have the balanced equation for this reaction:
AB3 ↔ A+3 + 3B-
So we can get Ksp:
when Ksp = [A+3][B-]^3
when [A+3] = 0.047 mol and from the balanced equation when
1 mol [A+3] → 3 mol [B-]
0.047 [A+3] → ??
[B-] = 3*0.047 = 0.141
so by substitution in Ksp formula:
∴Ksp = 0.047 * 0.141^3
= 1.32x10^-4
