There are approximately 160 grams in 1 mol of Fe2O3 molecules. Therefore, there would be 79/160= 0.49375 mols of Fe2O3 molecules in 79 grams. There are 5 atoms in total for each molecule of Fe2O3, therefore 79/160 * 5 = 79/32 = 2.46875 mols of atoms.
Explanation:
The partial pressure of an individual gas is equal to the total pressure of the mixture multiplied by the mole fraction of the gas.
Total pressure = 2atm
Mole Fraction = number of moles / total number of moles
Neon
Mole Fraction = 4.46 / 7.35 = 0.607
Partial Pressure = 0.607 * 2 = 1.214 atm
Argon
Mole Fraction = 0.74 / 7.35 = 0.101
Partial Pressure = 0.101 * 2 = 0.202 atm
Xenon
Mole Fraction = 2.15 / 7.35 = 0.293
Partial Pressure = 0.293 * 2 = 0.586 atm
Answer is: the atom is the smallest known particle of matter.
John Dalton claimed that atom is indestructible and a<span>ll atoms of a given element are identical in mass and properties.
</span>Thomson discovered electron and found the first evidence for isotopes<span> of a stable element.</span>
Answer:
1.58x10⁻⁵
2.51x10⁻⁸
0.0126
63.10
Explanation:
Phenolphthalein acts like a weak acid, so in aqueous solution, it has an acid form HIn, and the conjugate base In-, and the pH of it can be calculated by the Handerson-Halsebach equation:
pH = pKa + log[In-]/[HIn]
pKa = -logKa, and Ka is the equilibrium constant of the dissociation of the acid. [X] is the concentrantion of X. Thus,
i) pH = 4.9
4.9 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = - 4.8
[In-]/[HIn] = 
[In-]/[HIn] = 1.58x10⁻⁵
ii) pH = 2.1
2.1 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -7.6
[In-]/[HIn] = 
[In-]/[HIn] = 2.51x10⁻⁸
iii) pH = 7.8
7.8 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -1.9
[In-]/[HIn] = 
[In-]/[HIn] = 0.0126
iv) pH = 11.5
11.5 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = 1.8
[In-]/[HIn] = 
[In-]/[HIn] = 63.10
Answer:
In the nucleus of an atom ,there are protons & neutrons. Protons have charge of 1.6× 10^-19 C, while neutrons have 0C charges. Electrons orbit outside the atom. Their charge is - 1.6 ×10^-19C
Explanation:
