The molar mass of C2F4 (tetrafluoroethylene) is 100 g/mol. To find the number of moles of C2F4 in the specified quantity,
n = (5.85 g) / (100 g/mol) = 0.0585 mols C2F4
The calculation for the number of molecules per mole is done via the equation,
(0.0585 mols) x (6.022 x 10^23)
Given that each molecule contains 4 F atoms, then,
(0.0585 mols) x (6.022 x 10^23)(4)
= 1.41 x 10^23 atoms of F
The specific heat of titanium metal is 0.524 J/g°C. Given that Q = 1.68 kJ, which equates to 1680 Joules, with a mass of 126 grams and initial and final temperatures of 20°C and 45.4°C respectively, the specific heat is computed using the formula Q = (mass)(ΔT)(Cp), where ΔT = T₂ - T₁ = 25.4°C. Plugging in the numbers leads us to Cp = 0.524 J/g°C.
The calculation of moles of chromium (III) nitrate produced is done as follows. First, you write the reaction equation: 3 Pb(NO3)2 + 2 Cr = 2 Cr(NO3)3 + 3 Pb. Then, by using the mole ratio from Pb(NO3)2 to Cr(NO3)3, which is 3 to 2, you can find the moles of Cr(NO3)3. Thus, for 0.85 moles of lead (IV) nitrate, it equates to 0.85 x 2 / 3 = 0.57 moles.
Option 2: At [S] = Km, 50% of active sites are engaged by substrates.
