<span>The rate of a chemical reaction can be increased by raising the temperature. </span>
It should be the third one. "Science deals with facts, pseudoscience deals with theories"
•The atomic number of an atom is the number of protons it has. If the atomic number is 20 then we know the atom has 20 protons.
•The mass number of an atom is the total number of protons and neutrons the atom contains. The mass number is 41 and the number of protons is 20, just subtract 20 from 41 and you will get the number of neutrons: 41 - 20= 21. The atoms has 21 neutrons.
•The number of electrons found in an atom is equal to the number of protons. The atoms has 20 protons which means it has 20 electrons.
So, the answer is:
B) 20 protons, 20 electrons, and 21 neutrons
<span>Answer for the given question is CaBr2.
Although, the given equation requires balancing of by adding one more HBr and one more H2o in resultant. The given equation will product at least one CaBr2. Hence the answer for the given equation is Calcium bromide i.e. CaBr2.</span>
Answer: (2) decreasing the concentration of HCl(aq) to 0.1 M
Explanation: Rate of a reaction depends on following factors:
1. Size of the solute particles: If the reactant molecules are present in smaller size, surface of particles and decreasing the size increases the surface area of the solute particles. Hence, increasing the rate of a reaction.
2. Reactant concentration: The rate of the reaction is directly proportional to the concentration of reactants.
3. Temperature: Increasing the temperature increases the energy of the molecules and thus more molecules can react to give products and rate increases.
(1) Increasing the initial temperature to 25°C will increase the reaction rate.
(2) Decreasing the concentration of HCl(aq) to 0.1 M will decrease the reaction rate due to lesser concentration.
(3) Using 1.2 g of powdered Mg will increase the reaction rate due to large surface area.
(4) Using 2.4 g of Mg ribbon will increase the reaction rate due to high concentration of reactants.
