To determine the number of phosphorus atoms from a given mass, we need to determine the number of moles of the substance by dividing the molar mass which for in this case is equal to 123.88 g/mol for P4. Then, we multiply Avogadro's number. It <span>represents the number of
units in one mole of any substance. This has the value of 6.022 x 10^23 units /
mole.
mole P4 = 158 kg P4 ( 1000 g / 1 kg ) ( 1 mol / 123.88 g ) = 1275.43 mol P4
# of P4 atoms = 1275.43 mol P4 ( 6.022 x 10^23 atoms P4 / 1 mol P4 ) = 7.68x10^26 atoms P4</span>
Answer: Decreases across the period and increases down the group
It's mean the theory that changes in the earth's crust during geological history have resulted from the action of continuous and uniform processes.
Answer:
D. 0.3 M
Explanation:
NH4SH (s) <--> NH3 (g) + H2S (g)
Initial concentration 0.085mol/0.25L 0 0
Change in concentration -0.2M +0.2 M +0.2M
Equilibrium 0.035mol/0.25 L=0.14M 0.2M 0.2M
concentration
Change in concentration (NH4SH) = (0.085-0.035)mol/0.25L =0.2M
K = [NH3]*[H2S]/[NH4SH] = 0.2M*0.2M/0.14M ≈ 0.29 M ≈ 0.3M