Answer:
- The standard form of a chemical element is the natural mixture of several isotopes of the same element, which is atoms with the same number of protons but different number of neutrons, while an isotope is a particular kind of atom with a definite number of neutrons.
Explanation:
A <em>chemical element</em> is a pure substance formed by atoms with the same atomic number (number of protons). This is because it is the number of protons what identifies an element.
For example: oxygen is a chemical element, so oxygen is formed by only atoms of oxygen, and the atomic number of those atoms is 8, because every oxygen atom has 8 protons.
Nevertheless, some atoms of oxygen, may have different number of neutrons. Isotopes are different kind of atoms of the same element, which only differ in the number of neutrons. So, some atoms of oxygen will have 8 neutrons, other 9 neutrons, and other 10 neutrons (those are the stable isotopes of oxygen).
That difference in neutrons, is generally accepted that, does not modifiy substantially the chemical properties of the element, but the mass number. So, the isotopes with more neutrons wil be heavier, and the isotopes with less neutrons will be lighter.
- Mass number = number of protons + number of neutrons.
In general a chemical element is formed by a mixutre of isotopes of the same element.
Answer:
1. A) Its very dense
2. D) weight depends on gravity and mass is constant
3. C) Quart
4. D) 125 cubic cm
5. B) Attribute
Explanation:
Answer:
Yes
Explanation:
Bones sustain our bodies, and help shape our form. While very thin, the bones are large enough to bear all of our mass. Bones shield the organs of the body too. The skull supports the brain, and creates the face shape.
A standard solution is a solution (in this case sodium hydroxide) whose concentration (molarity) is known very precisely. <span>The molarity of the sodium hydroxide solution cannot be determined accurately because s</span>olid sodium hydroxide is highly hygroscopic (absorbs water from the air) and cannot be accurately weighed. Sodium hydroxide form sodium carbonate because it absorbs carbon
dioxide from the air.
The answer is liquid or solid.
That is a substance that forms a vapor is generally in liquid or solid physical state.
The substance that is in liquid or solid physical state, forms vapor.
When heated solid and liquid can be converted into vapor so the answer is solid or liquid is the physical state that forms vapors.
