The atomic number of Li is 3
Electron configuration of Li : 1s² 2s¹
The atomic number of Na is 11
Electron configuration of Na : 1s²2s²2p⁶3s¹
Thus there is one electron in the valence shell of Li (2s¹) and that of Na (3s¹). However, the valence electron in Na is in a shell that is farther away from the nucleus compared to that of Li. As a result, the Na valence electron will be held less tightly by the nucleus i.e. it will experience a reduced nuclear attraction and can be removed easily than the Li 2s electron.
Example:
Mass = ?
Density = 25 g/mL
Volume = 5 mL
therefore:
d = m / V
25 = m / 5
m = 25 x 5
m = 125 g
hope this helps!
Answer:
<span>Formula New Combination Predicted Formula
</span>
NaCl potassium + chlorine KCl
AlCl₃ aluminum + fluorine AlF₃
CO₂ tin + oxygen SnO₂
MgCl₂ calcium + bromine CaBr₂
HCl cesium + iodine CsI
<span>
CCl₄ silicon + bromine SiBr₄</span>
Explanation:
1) The question is incomplete. The first part is missing.
This is the first part of the question.
<span>Applying
the principle that the elements of a particular column in the Periodic
Table share the same chemical properties, complete the following chart.
The first one has been done for you.
</span>
2) This is the given chart:
<span>Formula New Combination Predicted Formula
</span>
Cu₂O silver + oxygen Ag₂O ← this is the example.
NaCl potassium + chlorine
<span>
AlCl₃ aluminum + fluorine </span>
CO₂ tin + oxygen
<span>
MgCl₂ calcium + bromine </span>
<span>
HCl cesium + iodine </span>
<span>
CCl₄ silicon + bromine
</span>
3) This is how you find the new formula to complete the chart.
i) NaCl potassium + chlorine
Since potassium is in the same group of sodium, you predict that in the new formula Na is replaced by K giving KCl.
ii) AlCl₃ aluminum + fluorine
Since fluorine is in the same group that Al, then you predict that in the new formula Cl is replaced by F leading to AlF₃
iii) CO₂ tin + oxygen
Since tin is in the same group that C, you predict that in the new formula C is replaced by Sn leading to SnO₂
iv) MgCl₂ calcium + bromine
Since calcium is in the same group that Mg, and bromine is in the same group that Cl, you predict thea in the new formula calcium replaces Mg and bromine replaces Cl, leading to CaBr₂
v) HCl cesium + iodine
Since H is in the same column that cesium and Cl is in the same colum that iodine, you predict that in the new formula Cs replaces H and I replaces Cl leading to: CsI
<span>
vi) CCl₄ silicon + bromine
</span>
Since silicon is in the same column that C and bromine is in the same column that Cl, you predict that in the new formula Si replaces C and Br replaces Cl, leading to SiBr₄
Answer:
The mass of reactants and products are equal hence the reaction obeys law of conservation of mass
Explanation:
The law of mass conservation states that for a closed system to all transfer of mass, the mass of system must remain constant over time. This means for a chemical reaction, the mass of reactants must equal the mass of products.
if 2.796g of Zn reacts with 2.414g of sulphur to produce 4.169g of ZnS ad 1.041g of unreacted sulphur, then it means that accorfing to the law of mass conservation, the mass of reactants (zinc and sulphur), must be equal to mass of products (zinc sulfide and unreacted sulphur)
Mass of reactants = 2.796g + 2.414g =5.21g
Mass of products = 4.169g + 1.041g=5.21g
