The answer is B, they differ greatly from the properties of all their elements. For example: Water is non-flamable but it is made from hydrogen, which is highly flammable, and oxygen, a gas that supports combustion.
Answer: -
C. Electrons
Explanation: -
Most of the space in an atom is empty. Through this space the electrons revolve around the centrally placed nucleus.
Inside the nucleus are present the protons and the neutrons. The nucleus size is very small compared to the rest of the atom.
Electrons carry negative charge, protons are positive and neutrons are neutral.
The correct answer is option B, that is, hypothesis.
A hypothesis refers to an anticipated illustration for an occurrence. It refers to a proposed illustration or a supposition made on the groundwork of inadequate proof as an initiation point for further investigation. In order for a hypothesis to be a scientific hypothesis, the scientific method needs that one can examine it.
The astronomical unit or also know as AU. Scientists use this because it’s convenient and easier to understand! Hope this helps ;)
Answer:
The molar concentration of Cu²⁺ in the initial solution is 6.964x10⁻⁴ M.
Explanation:
The first step to solving this problem is calculating the number of moles of Cu(NO₃)₂ added to the solution:

n = 1.375x10⁻⁵ mol
The second step is relating the number of moles to the signal. We know the the n calculated before is equivalent to a signal increase of 19.9 units (45.1-25.2):
1.375x10⁻⁵ mol _________ 19.9 units
x _________ 25.2 units
x = 1.741x10⁻⁵mol
Finally, we can calculate the Cu²⁺ concentration :
C = 1.741x10⁻⁵mol / 0.025 L
C = 6.964x10⁻⁴ M