13.6
a) yes Pb is more reactive that Ag, Pb before Ag
b) no, Cu after H
c) yes, Cl2 is more active than I2
4) yes, Mg is more active
13.7 (as I think)
Al ³⁺ more active than Zn²⁺, Mn can react with Zn²⁺, but not with Al ³⁺ , because Mn after Al but before Zn
<h3>
Answer:</h3>
B) 4H₂(g) + O₂(g) ⟶ 2H₂O(l)
<h3>
Explanation:</h3>
- Chemical reactions occur when compounds or elements combine to form new compounds or other elements.
- Chemical reactions may be classified into various types which include synthesis reactions, replacement reaction, decomposition reactions, and precipitation reactions among others.
- In our case, we were supposed to identify a synthesis reaction.
- Thus, we need to know what is a synthesis reaction.
- A synthesis reaction is a reaction that occurs when two elements or small compounds combine to generate a large compound.
- In this case, B is the choice that shows a synthesis reaction where hydrogen gas combines with oxygen gas to yield water.
Answer:
Mass = 55.52 g
Explanation:
Given data:
Number of atoms of Li = 4.81×10²⁴ atom
Number of grams = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For Li:
4.81×10²⁴ atom × 1 mol / 6.022 × 10²³ atom
8 moles
Mass in gram:
Mass = number of moles × molar mass
Mass = 8 mol × 6.94 g/mol
Mass = 55.52 g
Answer:
Pentafluorobenzene: 11,92 min
Benzene: 12,14 min
Explanation:
<em>Retention time of pentafluorobenzene is 12,98 min and 13,20 min of benzene.</em>
The adjusted retention time is the time an analyte spends in the column not the stationary phase. As time of unretained solute is 1,06 min the adjusted retention time for an analyte is:
tr' = tr - 1,06min
For pentafluorobenzene:
tr' = 12,98min - 1,06min = <em>11,92 min</em>
For benzene:
tr' = 13,20 - 1,06min = <em>12,14 min</em>
<em></em>
I hope it helps!
Each shell can contain only a fixed number of electrons: The first shell
can hold up to two electrons, the second shell can hold up to eight (2 +
6) electrons, the third shell can hold up to18 (2 + 6 + 10) and so on.
The general formula is that the nth shell can in principle hold up to
2(n2) electrons.