Answer:
Explanation:
70% (vol/vol) means
cotnaimns 70 %(vol/vol) 70 ml of isoprapnol is there in 100 ml of Rubbing sold alcohol.
if it is 200 ml then obvouly it has the 70*2 =140 ml of isoproanol required.
Given that,
Temperature, T = 1500 K
Wavelength, 
To find,
The energy of one photon of this light.
Solution,
We know that, the energy of a photon is given by the formula as follows :
So, the required energy is 
.
1) 0.89% m/v = 0.89 grams of NaCl / 100 ml of solution
=> 8.9 grams of NaCl in 1000 ml of solution = 8.9 grams of NaCl in 1 liter of solution
2) Molarity = M = number of moles of solute / liters of solution
=> calculate the number of moles of 8.9 grams of NaCl
3) molar mass of NaCl = 23.0 g /mol + 35.5 g/mol = 58.5 g / mol
4) number of moles of NaCl = mass / molar mass = 8.9 g / 58.5 g / mol = 0.152 mol
5) M = 0.152 mol NaCl / 1 liter solution = 0.152 M
Answer: 0.152 M
by sign convention Δ
is negative it means an exothermic reaction where the heat is lose so the temperature decreases.
Answer:
0.125 mole
Explanation:
From Avogadro's hypothesis, we discovered that 1 mole of any substance contains 6.02x10^23 atoms.
The statement above suggests that 1 mole of chromium contains 6.02x10^23 atoms.
Now, if 1mole of of chromium contains 6.02x10^23 atoms,
Then Xmol of chromium contains 7.52x10^22 atoms i.e
Xmol of chromium = 7.52x10^22/6.02x10^23
Xmol of chromium = 0.125 mole
Therefore, 0.125 mole of chromium contains 7.52x10^22 atoms
