<span>If I done the math correctly it is 3729J because you multiply 16.5 g by the 2260 J/g and get 3729 J</span>
Answer:
Na₂₆F₁₁
Explanation:
We find the moles of the substance assuming 100 g of the substance is present. Why do we take 100 g? Because then the percent of sodium/fluorine, would be the g of sodium/fluorine respectively:
74.186 g Sodium | 1 mol Sodium/23 g => 3.2255 mol Na
25.814 g Fluorine | 1 mol Fluorine/19 g => 1.3586 mol F
Divide each by smallest number of moles:
3.2255/1.3586 = 2.37
1.3586/1.3586 = 1
Multiply by common number to get a smallest whole number:
2.37*11 = 26,
1*11 = 11
The empirical formula is Na₂₆F₁₁
Answer:
different species
Explanation:
weeds and vegetables are both plants, but they are completely different types of plants.
Answer:
pH = 12.2
Explanation:
Given data:
Mass of lime = 0.69 g
Volume = 1535 mL (1535 / 1000 = 1.535 L)
pH of solution = ?
Solution:
First of all we will determine the molarity.
Molarity = moles of solute / volume in litter
Number of moles = mass / molar mass
Number of moles = 0.69 g / 56.1 g/mol
Number of moles = 0.0123 mol
Molarity = moles of solute / volume in litter
Molarity = 0.0123 mol / 1.535 L
Molarity = 0.008 M
One mole of CaO neutralize two mole of OH⁻.
0.008 M×2 = 0.016 M
[OH⁻] = 0.016 M
pOH = -log [OH⁻]
pOH = [0.016]
pOH = 1.8
14 = pH +pOH
pH = 14 - pOH
pH = 14-1.8
pH = 12.2