Answer:
This question appear incomplete
Explanation:
This question appear incomplete because an equation to show the production of sodium chloride from calcium chloride should have been illustrated. However, if the balanced chemical equation showing sodium chloride (NaCl) been a product of a reaction involving calcium chloride (CaCl₂) as a reactant (shown below) is to be used, then we start by writing a complete balanced chemical equation
CaCl₂ + Na₂CO₃ ⇒ CaCO₃ + 2NaCl
From the equation above, it can be deduced that 1 mole of CaCl₂ is required to produce 2 moles of NaCl, thus how many moles of CaCl₂ will be required to produce 6.5 moles of NaCl.
1 mole of CaCl₂ = 2 moles of NaCl
? moles of CaCl₂ = 6.5 moles of NaCl
cross multiply
? moles of CaCl₂ = 6.5 × 1/2
? moles of CaCl₂ = 3.25 moles of CaCl₂
3.25 moles of CaCl₂ will be needed to produce 6.5 moles of NaCl
Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass.
Answer:
B is the answer because it doesn't matches the num of valence electrons
The only solution you'll need to have for this problem is a periodic table. The columns in the table are called groups, and they are number from the left to the right starting with 1. The rows in the table are called periods which are numbered from the top to bottom starting with 1.
6. Elements that belong to the same group portray similar chemical properties. Therefore, the element in period 4 which is also in group 2 is
<em>Calcium (Ca)</em>.
7. The elements that are striked through with the red slanting lines are the metalloids. All the elements to the left of the metalloids are metals. All the elements to the right are nonmetals. Bromine has a symbol of Br. Since At is a metalloid and located in the same group with Br, the
<em>answer is Astatine (At).</em>8. Tin has the chemical symbol of Sn. The nonmetal that is located in the same group is
<em>Carbon (C)</em>.
9. All the elements in period 6 would have similar properties. The answers could be:
<em>Phosphorus (P), Arsenic (As), Antimony (Sb) and Bismuth (Bi)</em>.
10. Period is row 1 and group 18 is the last column.
<em>The answer is Helium (He).</em>