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.
Answer:
The force of gravity acting on the car is <u>9800 N vertically downward.</u>
Explanation:
Given:
Mass of the car given is 1000 kg.
We know that the force of gravity is the force applied by the center of Earth on any body. The force of gravity is also called the weight of the body and always act towards the center of the Earth.
From Newton's second law, we know that the force acting on a body is equal to its mass and acceleration.
Here, the acceleration acting on the car is due to gravity and thus has a constant value of 9.8 m/s² on the surface of Earth.
Therefore, the force of gravity acting on the car is given using the Newton's second law as:
Force of gravity = Mass of car 
Acceleration due to gravity.
Force of gravity = (1000 kg) (9.8 m/s²)
Force of gravity = 9800 N [1 kg.m/s² = 1 N]
Therefore, the force of gravity acting on the car is 9800 N vertically downward.
Answer:
motion is the phenomenon in which an object changes its position over time. Motion is mathematically described in terms of displacement, distance, velocity, acceleration, speed, and time.
Explanation:
Answer:
One change of state happens when you add energy to the substance. This change of state is called melting. By adding energy to the molecules in a solid the molecules begin to move quicker and can break away from the other molecules. ... The temperature at which a substance goes from a solid to a liquid is it melting point.
