I got you
The molecular formula for the combustion of butane in oxygen is:
2 C4H10 + 13 O2 ---> 8 CO2 + 10 H20
<span>You take the mass of carbon dioxide, 56.8g, divide by its molar mass, 44.01g/mol, to produce the moles of carbon dioxide. This is multiplied by the molar ratio of butane/CO2, (2/8) = 1/4, which gives the moles of butane required to produce the carbon dioxide. Multiply the number of moles of butane by its molar mass, 58.12g/mol, to produce the mass of butane. Mass of butane = 18.8g</span>
Helium - 4 isotope has 2 protons and 2 neutrons.
Its atomic number is 2 (the number of protons). Atomic number is the number of protons in the atom of an element and it identifies the element. All the isotopes of an element have the same atomic number (same number of protons). So, all the isotopes of hellium have 2 protons.
The number 4 that identifies the helium - 4 isotope is the mass number, i.e. the number of protons plus the number of neutron. So, helium-4 isotope has 2 protons and 2 neutrons. While, other isotopes of helium have 2 protons but different number of neutrons.
The atomic number enable us to deduce the number of electrons in an atom because the atoms are neutral, which implies that the positive and negative charge are equal. Given that the magnitude of the charge of electons and protons are equal but the sign is opposed (protons are positve and electrons are negative) the number of electrons in the atom equals the number of protonts. That is why the atomic number is also the number of electrons of the atom.
Draw eight circles and nine more in a big circle = this represents your nucleus
draw eight electrons (since electrons = protons in neutral elements) outside of it (2 in one ring, then 6 in a second ring)
Answer:
As we have already discussed, reactivity of alkali metals tends to increase as you go down the group. Therefore, sodium is less reactive with water than is potassium, likewise with the alkaline metals; calcium is more reactive than magnesium
Explanation:
A process in which water vapor changes into liquid state is known as condensation. As we know that when energy is released in a reaction then it is known as exothermic reaction and when energy is absorbed in a reaction then it is known as endothermic reaction.
As vapors have high energy so, when they change into liquid state then heat energy is released by them. Therefore, condensation is an exothermic reaction.
As per Le Chatelier's principle, any disturbance caused in an equilibrium reaction will tend to shift the equilibrium in a direction away from the disturbance.
So, when there will occur a decrease in temperature then molecules of a gas will come closer to each other. Hence, there will also occur a decrease in vapor pressure of the gas.