Answer:
154 g
Explanation:
Step 1: Write the balanced decomposition equation
2 NaN₃(s) ⇒ 2 Na(s) + 3 N₂(g)
Step 2: Calculate the moles corresponding to 79.5 L of N₂ at STP
At STP, 1 mole of N₂ occupies 22.4 L.
79.5 L × 1 mol/22.4 L = 3.55 mol
Step 3: Calculate the number of moles of NaN₃ needed to form 3.55 moles of N₂
The molar ratio of NaN₃ to N₂ is 2:3. The moles of NaN₃ needed are 2/3 × 3.55 mol = 2.37 mol.
Step 4: Calculate the mass corresponding to 2.37 moles of NaN₃
The molar mass of NaN₃ is 65.01 g/mol.
2.37 mol × 65.01 g/mol = 154 g
By crushing a solid into a powder you increase the reaction rate (the chemical reaction rate). By crushing into a powder, you are increasing the surface area, increasing the exposure to the chemical reaction. The smaller the particles, the faster the chemical reaction that will take place. Think about an ice cube put in a pot of boiling water. The whole ice cube will take longer to melt than if you first crushed that ice cube into small pieces. Small pieces of ice put into boiling water would melt very quickly.
Hope this helps!! :)
Answer:
See note in Explanation
Explanation:
The modern periodic table of the elements is arranged in order of increasing atomic numbers which is also in terms of the number of protons in the nucleus. That is, for any element listed on the periodic table its atomic number equals the number of protons in the nucleus. Thus, the element with 2 protons in its nucleus would be element #2 (Helium), element #3 (Lithium) has 3 protons in its nucleus and element #4 (Beryllium) has an atomic number 4 and contains 4 protons in its nucleus.
Also, this arrangement of elements finds that elements <u>below</u> elements 2, 3 & 4, Neon #10; sodium #11 & magnesium #12 have similar chemical and physical properties as does elements #2, #3 & #4. Such gives rise to the 'Periodic Law' => the chemical and physical properties of the elements is a periodic function of their atomic number (or, number of protons in the nucleus).
So Helium walks into a bar and orders a beer...
The bartender says, "Sorry we don't serve noble gases here."
Helium doesn't react.
Ten protons would be Neon, but the most stable? I'd have to say 12 neutrons in contrast to the 10 protons. Not too negative in balance.