Answer:
20 mole of oxygen
Explanation:
1 mole of proprane reacts with 5 moles of oxygen so 4 time 5 equals 20
Döbereiner grouped the known elements into <em>triads</em> (sets of three) so that
• The <em>atomic mass of the middle element</em> was approximately the average of the other two
• The <em>chemical properties of the middle element</em> were between those of the other two
• The <em>physical properties of the middle element</em> were between those of the other two
One example of a triad is Li – Na – K.
(a) Atomic mass of Na = 23.0 u
Average atomic mass of Li and K = (6.9 u + 39.1 u)/2 = 46.0 u/2 = 23.0 u
(b) Li reacts slowly with water. Na reacts rapidly. Potassium reacts violently.
(c) Melting point of Na = 371 °C.
Average melting point of Li and K = (454 °C + 330 °C)/2 = 784 °C/2
= 392 °C
Answer:
2NaBr + I2 Right arrow. 2NaI + Br2
2AgNO3 + Ni Right arrow. Ni(NO3)2 + 2Ag
Explanation:
The activity or electrochemical series is an arrangement of elements according to their order
of reactivity.
If we look at the reactions, one thing that we must note is that the reactions that can occur are those in which an element that is higher in the series displaces another element that is lower in the series.
Br is higher in the electrochemical series than I so it can displace it. Ni is higher than Ag in the electrochemical series hence it can displace it.
Density= mass/volume aluminum can= 174 •g/ 4 • cm ^3. =2.76•g•cm ^-3
