<span> red litmus paper turns </span>blue <span>under basic or alkaline conditions, with the color change occurring over the pH range 4.5–8.3 at 25 °C (77 °F). Neutral litmus paper is purple.</span>
The answer is : 17.5 liters drained and replaced by 17.5 liters of 100% solution.
x = amount drained and replaced
(70-x) = remaining amount of 20% solution
<span>.20(70-x) + 1.00(x) = .40(70)
14 - .2x + 1x = 28
1x - .2x = 28 - 14
</span><span>.8x = 14
</span><span>x = 14/.8
x= 17,5 ( 17.5 liters drained and replaced by 17.5 liters of 100% solution)
</span>
Answer: A
Explanation: Protons and neutrons form the nucleus of the atom, with electrons orbiting it.
Answer:
The answer to your question is: 0.25 l
Explanation:
Data
P1 = 1 atm
V1 = 0.5 l
P2 =2 atm
V2 = ?
T = constant
Formula
V1P1 = V2P2
Clear V2 from the formula
V2 = V1P1/P2
Substitution
V2 = (0.5)(1)/2 substitution
= 0.25 l result
This sounds very much like a chicken-egg problem.
The first thing that formed must be hydrogen nuclei. The only other alternative is that the atom was created instantly, and the nuclei sprang forth at the same time as the atom, meaning that neither was technically first. The logic is that an atom can’t form without a nucleus, but it theoretically could be created instantly.