Protists belong to the group eukaryotes (having their DNA enclosed
inside the nucleus). They are not plants, nimals or fungi but they act like
one. They can be in general subgroups such as unicellular algae, protozoa and
molds. They thrive in environments with little sunlight. The answer is
letter B.
Answer:
11) the difference in heat energies between products and reactants
12) enthalpy change
Explanation:
The heat of reaction is defined as that energy released or absorbed as chemical substances participate in a chemical reaction. It is a term used to denote the change in energy as reactants change into products.
Another name of heat of reaction is enthalpy of reaction. It is a state function since it depends on the initial and final states of the system.
Answer:
Explanation:
We are given a number of particles and asked to convert to moles.
<h3>1. Convert Particles to Moles </h3>
1 mole of any substance contains the same number of particles (atoms, molecules, formula units) : 6.022 *10²³ or Avogadro's Number. For this question, the particles are not specified.
So, we know that 1 mole of this substance contains 6.022 *10²³ particles. Let's set up a ratio.
We are converting 2.98*10²³ particles to moles, so we multiply the ratio by that value.
The units of particles cancel.
<h3>2. Round</h3>
The original measurement of particles (2.98*10²³) has 3 significant figures, so our answer must have the same.
For the number we found, 3 sig figs is the thousandth place.
The 8 in the ten-thousandth place (0.4948522086) tells us to round the 4 up to a 5 in the thousandth place.
2.98*10²³ particles are equal to approximately <u>0.495 moles.</u>
<h3>During physical changes, the composition od the original substance is not altered, but the properties of the original substance are altered. During a chemical change the composition od the original substance is not altered and the change is irreversible. Melting of butter and wax is an example of chemical changes.</h3>
The correct answer among the choices given is the last option. A mixture has particles that cannot be seen but do reflect light. It should be classified as a colloid. A colloid is a mixture in which one substance is suspended throughout another substance.
