Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in acidic solutions and pink in basic solutions. Phenolphthalein is slightly soluble in water and usually is dissolved in alcohols for use in experiments.
Answer:
The new temperature is 373 K
Explanation:
Step 1: Data given
Volume air = 5000 mL = 5.0 L
Temperature = 223K
New volume = 8.36 L
Step 2: Calculate the new temperature
V1/T1 = V2/T2
⇒V1 = the initial volume = 5.0 L
⇒T1 = the initial temperature = 223 K
⇒V2 = the new volume = 8.36 L
⇒T2 = the new temperature
5.0/223 = 8.36 /T2
T2 = 373 K
The new temperature is 373 K
After 25 days, it remains radon 5.9x10^5 atoms.
Half-life is the time required for a quantity (in this example number of radioactive radon) to reduce to half its initial value.
N(Ra) = 5.7×10^7; initial number of radon atoms
t1/2(Ra) = 3.8 days; the half-life of the radon is 3.8 days
n = 25 days / 3.8 days
n = 6.58; number of half-lifes of radon
N1(Ra) = N(Ra) x (1/2)^n
N1(Ra) = 5.7×10^7 x (1/2)^6.58
N1(Ra) = 5.9x10^5; number of radon atoms after 25 days
The half-life is independent of initial concentration (size of the sample).
More about half-life: brainly.com/question/1160651
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Answer:C. The value of n for H+(H2O)n can be calculated for almost all solutions.
Explanation:
An hydrate can be described as a substance that contains water or with an hydrogen bonded water molecule group.
The hydrate group doesn't necessarily have a fixed formula.