A. By ensuring they follow the scientific method
True. An exothermic reaction gives off heat. In this case it's a combustion reaction of wood and oxygen.
Answer:
a. Approximate umber of atoms = 10¹¹
b. number of atoms = 50 atoms thick
Note: The question is missing some parts. The complete question is as follows; Calculate the approximate number of atoms in a bacterium. Assume that the average mass of an atom in the bacterium is ten times the mass of a hydrogen atom. (Hint: The mass of a hydrogen atom is on the order of 1×10⁻²⁷ kg and the mass of a bacterium is on the order of 1×10⁻¹⁵ kg)
Explanation:
a. Approximate umber of atoms = mass of bacterium / 10 * mass of hydrogen
number of atoms = 10⁻⁵/ 10 × 10⁻²⁷
number of atoms = 10¹¹ atoms
b. The cell membrane is 10-8 m thick while the hydrogen atom has a diameter of 10-10 m.
The number of atoms in the cell membrane = d1 / 2 × d2
where d1 = diameter of cell membrane; d2 = diameter of hydrogen atom
The number of atoms in the cell membrane = 10⁻ / 2 × 10⁻¹⁰ = 50 atoms
The change in the state of matter causes change in the motion of the particles of the matter. The gaseous state of matter has the greatest speed while the solid state has the least speed.
The change in state of every matter is accompanied by lost or gained of energy.
Example is water.
The solid state of water is ice. The motion of particles of the water is relatively zero because the molecules are held at a fixed position.
The liquid state of water occurs when the temperature of the ice is increased above zero degree Celsius. The speed of the particles of water in liquid state is greater than solid state.
The gaseous state of water occurs when the temperature of the liquid water is increased beyond 100 degree Celsius. The speed of water in gaseous state is greater than liquid state.
Learn more about different state of matter here: brainly.com/question/9402776