They are all stable and have eight valence electrons
Answer: 4Kcal
Explanation:
H= mcø
M=200g
C= 1 cal/g/°c
Ø= 40-20=20°c
H= 200*1*20= 4000calories= 4Kcal
Answer:
1.00 × 10¹⁸
Explanation:
1. Calculate the <em>energy of one photon</em>
The formula for the energy of a photon is
<em>E</em> = <em>hc</em>/λ
<em>h</em> = 6.626 × 10⁻³⁴ J·s; <em>c</em> = 2.998 × 10⁸ m·s⁻¹
λ = 477 nm = 477 × 10⁻⁹ m Insert the values
<em>E</em> = (6.626 × 10⁻³⁴ × 2.998× 10⁸)/(477 × 10⁻⁹)
<em>E</em> = 4.165× 10⁻¹⁹ J
2. Calculate the <em>number of photons</em>
Divide the total energy by the energy of one photon.
No. of photons = 0.418 × 1/4.165 × 10⁻¹⁹
No. of photons = 1.00 × 10¹⁸
The balanced thermochemical equation is
KBr ------- K + 1/2 Br2
<h3>What is thermochemical equation? </h3>
A Thermochemical Equation is defined as the balanced stoichiometric chemical equation which includes the enthalpy change, ΔH.
The chemical equation for the decomposition of potassium bromide to its constituent elements bromine ans potassium :
KBr ----- K + Br2
The balanced thermochemical equation of the decomposition of potassium bromide to its constituent elements potassium and bromide as follows
KBr ------- K + 1/2 Br2
As the heat is absorbed in this reaction therefore, heat is positive.
Thus, we concluded that the balanced thermochemical equation is
KBr ------- K + 1/2 Br2
learn more about thermochemical equation:
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