Materials<span> and their </span>properties<span>: </span>compounds like<span> sodium chloride - an interactive educational resource for 11 to 14 year olds. ... Elements are substances (</span>like<span> hydrogen and oxygen) that can't be split into simpler substances. ... For </span>each<span> statement, decide whether it describes a mixture or a </span>compound<span> and check the box.</span>
To get out the iron filings put everything in to a container and then put the magnet to the side to attract them. Pull them out of the container. Then, I don’t know how to separate the sand and salt. Maybe evaporate the salt? I joke you can figure it out. Best of luck! :)
Answer:
Explanation:
formula of osmotic pressure is as follows
p= n RT
n is mole of solute per unit volume
If m be the grams of solute needed
m gram = m / 227.1 moles
m / 227.1 moles dissolved in .279 litres
n = m / (227.1 x .279 )
= m / 63.36
substituting the values in the osmotic pressure formula
5.14 = (m / 63.36) x .082 x 298
m / 63.36 = .21
m = 13.32 grams .
Answer:
First, precipitate of AgCl is formed. Second, a soluble complex of silver and ammonia is formed. Third, AgCl is reproduced due to disappearance of ammonia complex in presence of 
.
Explanation:
In presence of NaCl, 
forms an insoluble precipitate of AgCl.
Reaction: 
In presence of 
, AgCl gets dissolved into solution due to formation of soluble ![[Ag(NH_{3})_{2}]^{+}](https://tex.z-dn.net/?f=%5BAg%28NH_%7B3%7D%29_%7B2%7D%5D%5E%7B%2B%7D)
complex.
Reaction: ![AgCl(s)+2NH_{3}(aq.)\rightarrow [Ag(NH_{3})_{2}]^{+}(aq.)+ Cl^{-}(aq.)](https://tex.z-dn.net/?f=AgCl%28s%29%2B2NH_%7B3%7D%28aq.%29%5Crightarrow%20%5BAg%28NH_%7B3%7D%29_%7B2%7D%5D%5E%7B%2B%7D%28aq.%29%2B%20Cl%5E%7B-%7D%28aq.%29)
In presence of , complex gets destroyed and free 
again reacts with free 
to produce insoluble AgCl
Reaction: ![[Ag(NH_{3})_{2}]^{+}(aq.)+2H^{+}(aq.)+Cl^{-}(aq.)\rightarrow AgCl(s)+2NH_{4}^{+}(aq.)](https://tex.z-dn.net/?f=%5BAg%28NH_%7B3%7D%29_%7B2%7D%5D%5E%7B%2B%7D%28aq.%29%2B2H%5E%7B%2B%7D%28aq.%29%2BCl%5E%7B-%7D%28aq.%29%5Crightarrow%20AgCl%28s%29%2B2NH_%7B4%7D%5E%7B%2B%7D%28aq.%29)
Ln(800/3200) = - kt
t = 24 years.
ln(0.25) = -k*24
(- 1.3863) = -k*24
1.3863 / 24 = k
0.05776 = k
ln(0.5) = -k*t
-0.6931 = - 0.05776 t
12 = t
I don't know if you can just look at the question and know the answer. If 24 years is a quarter life then is it obvious that the 1/2 life is 12 years? It might be, but the method I've used works for sure.
