In order to answer this, we mus know the data for the heat of combustion of propane. This is an empirical data that you can search online. The heat of combustion is -2220 kJ/mol. The molar mass of propane of 44.1 g/mol. The solution is as follows:
ΔH = -2220 kJ/mol (1 mol/44.1 g)(1000g/1kg)(20 kg)
<em>ΔH = -1006802.721 kJ or -1 GJ</em>
Electrons are emitted from the surface of a metal in photoelectric effect.
<h3>What is the photoelectric effect?</h3>
The photoelectric effect is the emission of electron from the surface of a metal when light is shone on the surface..
For electrons to be emitted, the light must have a certain frequency known as threshhold frequency.
Therefore, electrons are emitted from the surface of a metal in photoelectric effect.
Learn more about photoelectric effect at: brainly.com/question/21320305
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Answer:
A balanced chemical equation must always include coefficients on every reactant and product.
Explanation:
<u>A balanced chemical equation does not need to include coefficients on every reactant and product.</u>
For example, below is a balanced chemical equation in which the reactants and the products have no coefficients whatsoever:
NaOH(aq) + HCl (aq) -----> NaCl (s) + H2O (l)
<em>Of course, a properly written chemical equation must include the states of matter of all the substances in the reaction and the number of atoms of each element must balance both in the reactant and product sides of the equation. Generally, a balanced chemical equation must obey the law of conservation of matter which opines that matter can neither be created nor destroyed but can only be converted from one form to another. </em>
Hence, that a balanced chemical equation must always include coefficients on every reactant and product is not true.
By measuring them, by monitoring them, or by separating them.
Answer:
The kinetic theory of matter (particle theory) says that all matter consists of many, very small particles which are constantly moving or in a continual state of motion. The degree to which the particles move is determined by the amount of energy they have and their relationship to other particles.
Six main points of the particle theory:
• All matter is made of particles.
• Particles have space between them.
• Particles are always moving.
• Particles move faster and get farther apart when heated.
• Particles are attracted to each other.
• All Particles of the same substance are identical
