266000 = 2.66 x 10^5
hope this helps
Answer:
Hope it helped
Explanation:
For neutral atoms, the number of valence electrons is equal to the atom's main group number. The main group number for an element can be found from its column on the periodic table. For example, carbon is in group 4 and has 4 valence electrons. Oxygen is in group 6 and has 6 valence electrons.
Answer:
d.3.0
Explanation:
Step 1: Calculate the final volume of the solution
The final volume is equal to the sum of the volumes of the initial HCl solution and the volume of distilled water.
V₂ = 100 mL + 100 mL = 200 mL
Step 2: Calculate the final concentration of HCl
We will use the dilution rule.
C₁ × V₁ = C₂ × V₂
C₂ = C₁ × V₁/V₂ = 0.002 M × 100 mL/200 mL = 0.001 M
Step 3: Calculate the pH of the final HCl solution
Since HCl is a strong acid, [H⁺] = HCl. We will use the definition of pH.
pH = -log [H⁺] = -log 0.001 = 3
<span>(a) Assuming the amount of O2(g) is not limiting the reaction, a mass of 4.23g of Ca(s) will produce an equal mass of CaO(s), hence it will produce 4.23g of CaO(s).
According to their respective molar masses, we have the following CaO molar mass :
Molar mass of Ca + Molar mass of O = 40.1 + 16 = 56.1 g/mol
4.23g of Ca will then produce : 4.23 / 56.1 = 0,07540107 mol of CaO.
(b) With the same reasonment as above, and assuming the amount of Ca is not limiting, we have :
2.87g of O2 will produce : 2.87 / 56.1 = 0,051158645 mol of CaO.
(c) From (a) and (b) answers, we can conclude that the reactant that produces less mol of CaO is limiting the reaction. Hence following the given masses, O2 is the limiting reactant.
(d) Knowing the molar mass of CaO is 56.1 g/mol and knowing that O2 is the limiting reactant, we also know the reaction can produce a maximum of 0,051158645 mol of CaO can be produced.
So we can conclude we will produce :
56.1 * 0,051158645 = 2.87g of CaO.</span>
