M IS A LETTER but N is a letter
Answer:
The reaction is exothermic (option 4)
Explanation:
P4 + 5O2 → P4O10 + 712 kcal
In chemical reactions heat can be absorbed or released:
⇒in the first case, when heat is absorbed, this is called an endothermic reaction. The products have more energy than the reactants. The reaction requires or absorbs energy from it's surroundings. That means that in this reaction energy , in the form of heat, will be absorbed by the reactants.
⇒ when heat is released, this is called an exothermic reaction. The reactants have more energy than the products. The reaction gives or releases energy to it's surroundings. That means that in this reaction energy , in the form of heat, will be released by the reactants.
in the case of P4 + 5O2 → P4O10 + 712 kcal
We notice that on the right side, which is the product side, there is a positive amount of energy. This means that the energy is released by the the reactants, in this reaction. <u>The reaction is exothermic.</u>
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Answer:
Atoms are composed of a central nucleus which is surrounded by orbiting <u>Electrons</u>.
Explanation:
The word Atom is derived from atomos meaning indivisible particle. An atom is a very small sized particle and its size is approximately 100 picometers.
Atoms are composed of a Nucleus which contains protons and neutrons and the nucleus is surrounded by orbiting electrons. Also, the nucleus is positively charged due to +ve protons and the electrons revolving around nucleus are -vely charged making overall atom neutral in nature.
Atoms react with another atoms due to the presence of valence electrons present in the valence shell of an atom. The valence electrons would make a covalent bond by mutually sharing the electrons or it may form an ionic bond by gaining and loosing valence electron.
Answer:
should be B
because the player has more mass than the puck
Explanation:
Answer: The theoretical yield of aspirin is 4.14 g
Explanation:
To calculate the moles :
mass of acetic anhydride = 
According to stoichiometry :
1 mole of salycylic acid require 1 mole of acetic anhydride
Thus 0.023 moles of salycylic acid require=
of acetic anhydride
Thus salycylic acid is the limiting reagent as it limits the formation of product and acetic anhydride is the excess reagent.
As 1 mole of salycylic give = 1 mole of aspirin
Thus 0.023 moles of salycylic acid give = of aspirin
Mass of aspirin = 
Thus theoretical yield of aspirin is 4.14 g
