Answer:
676mmHg
Explanation:
Using the formula;
P1/T1 = P2/T2
Where;
P1 = initial pressure (mmHg)
P2 = final pressure (mmHg)
T1 = initial temperature (K)
T2 = final temperature (K)
According to the information provided in this question;
P1 = 725.0mmHg
P2 = ?
T1 = 20°C = 20 + 273 = 293K
T2 = 0°C = 0 + 273 = 273K
Using P1/T1 = P2/T2
725/293 = P2/273
Cross multiply
725 × 273 = 293 × P2
197925 = 293P2
P2 = 197925 ÷ 293
P2 = 676mmHg.
The resulting pressure is 676mmHg
Answer:
Yes, it is possible. Let us consider an example of two solutions, that is, solution A having 20 percent mass RbCl (rubidium chloride) and solution B is having 15 percent by mass NaCl or sodium chloride.
It is found that solution A is having more concentration in comparison to solution B in terms of mass percent. The formula for mass percent is,
% by mass = mass of solute/mass of solution * 100
Now the formula for molality is,
Molality = weight of solute/molecular weight of solute * 1000/ weight of solvent in grams
Now molality of solution A is,
m = 20/121 * 1000/80 (molecular weight of RbCl is 121 grams per mole)
m = 2.07
Now the molality of solution B is,
m = 15/58.5 * 1000/85
m = 3.02
Therefore, in terms of molality, the solution B is having greater concentration (3.02) in comparison to solution A (2.07).
Explanation:
Medieval number one. There you havt it.
Mass box C is 10+5. (So C is 15)
But if C was 30, how many times could you put B (5) into it?
30/5 = 6
You would need 6 boxes of B to make 30 grams of C.
Reactivity trends of halogen:
1) Melting point and boiling points increased down the
group
2) Colour becomes darker.
E.g. Fluorine (pale yellow)
Chlorine (yellowish-green)
Bromine (reddish-brown)
Iodine (purplish-black)
Astatine (black)
3) The reactivity decreases down the group.
Reactivity:
F > Cl > Br > I > At
