Answer:
a solution color becoming less intense due to dilution- is not an evidence of a chemical reaction
bubbles (gas formation) - evidence of a chemical reaction
explosion or fire - evidence of a chemical reaction
changes in color- evidence of a chemical reaction
precipitation- evidence of a chemical reaction
changes in temperature - evidence of a chemical reaction
a solid liquifying - is not an evidence of a chemical reaction
solution colors mixing - is not an evidence of a chemical reaction
Explanation:
A chemical change is not easily reversible and yields new substances. It is often accompanied by a loss or gain of heat.
In the answer section, i have shown some evidences that lead us to conclude that a chemical reaction has taken place. The occurrence of a chemical change often goes with the formation of new substances as earlier stated and any of these signs may accompany the process.
For instance, when a metal is dropped in dilute acid solution, bubble of hydrogen gas indicates that a chemical reaction has taken place.
Answer:
Increasing the surface area of a reactant increases the frequency of collisions and increases the reaction rate. Several smaller particles have more surface area than one large particle. The more surface area that is available for particles to collide, the faster the reaction will occur.
Explanation:
:)
The SI unit for amount<span> of </span>substance<span> is the </span>mole<span>. It has the unit symbol mol. The proportionality constant is the inverse of the Avogadro constant. The </span>mole<span> is defined as the </span>amount<span> of </span>substance that contains<span> an equal </span>number<span> of elementary entities as there are </span>atoms in 12g<span> of the </span>isotope<span> carbon-</span>12<span>.
Hope This Helped! :3</span>
Answer: option d. all of the above.
Explanation:
A mineral is an element or a inorganic compound that existes in nature as solid cristals; usually combined with other minerals in ores.
Some examples of minerals, among many, are titania, wich is TiO2, zirconia, which is ZrO2, silica, which is SiO2, gold, Au, silver, Ag.
As you see the definition and examples given meet the whole features included in the stament: a. the have a chemical formula, b they occur naturally, and c.have a characteristic internal structure (that is the way how the atoms are arranged in the specifi cristal).
Answer:
The correct answer is no.
Explanation:
Tellurium is a chemical element denoted by Te and having atomic number 52. It is mildly toxic, brittle, silver-white, and rare metalloid. The element is chemically related to sulfur and selenium, all three of which are chalcogens.
Oxygen is a chemical element, that is, a substance, which comprises only one kind of atom. Its official chemical symbol is O and exhibits an atomic number 8, this signifies that an atom of oxygen possesses eight protons in its nucleus. In the given question, it is not likely that tellurium would replace for oxygen, as the two elements are highly unlike.