The answer is B. a flashlight uses a battery to operate.
The battery represents the chemical energy. This is converted into electricity, which is converted into light energy.
A gas made up of atoms escapes through a pinhole 0.225times as fast as gas. Write the chemical formula of the gas.
Answer:
Explanation:
To solve this problem, we must apply Graham's law of diffusion. This law states that "the rate of diffusion or effusion of a gas is inversely proportional to the square root of its molecular mass at constant temperature and pressure".
Mathematically;
r₁ is the rate of diffusion of gas 1
r₂ is the rate of diffusion of gas 2
m₁ is the molar mass of gas 1
m₂ is the molar mass of gas 2
let gas 2 be the given H₂;
molar mass of H₂ = 2 x 1 = 2gmol⁻¹
rate of diffusion is 0.225;
i .e r1/r2 = 0.225
0.225 = √2 / √ m₁
0.225 = 1.414 / √ m₁
√ m₁ = 6.3
m₁ = 6.3² = 39.5g/mol
The gas is likely Argon since argon has similar molecular mass
The molecule BH3 is trigonal planar, with B in the center and H in the three vertices. Ther are no free electrons. All the valence electrons are paired in and forming bonds.
There are four kind of intermolecular attractions: ionic, hydrogen bonds, polar and dispersion forces.
B and H have very similar electronegativities, Boron's electronegativity is 2.0 and Hydrogen's electronegativity is 2.0.
The basis of ionic compounds are ions and the basis of polar compounds are dipoles.
The very similar electronegativities means that B and H will not form either ions or dipoles. So, that discards the possibility of finding ionic or polar interactions.
Regarding, hydrogen bonds, that only happens when hydrogen bonds to O, N or F atoms. This is not the case, so you are sure that there are not hydrogen bonds.
When this is the case, the only intermolecular force is dispersion interaction, which present in all molecules.
Then, the answer is dispersion interaction.
Base is Ca(OH)2.
Acid is H3PO4.
First part of the salt comes from base,
second par comes from the acid.
