Answer:
The concentration of the solution is 1.364 molar.
Explanation:
Volume of perchloric acid = 29.1 mL
Mass of the solution = m
Density of the solution = 1.67 g/mL

Percentage of perchloric acid in 48.597 solution :70.5 %
Mass of perchloric acid in 48.597 solution :
= 
Moles of perchloric acid = 
In 29.1 mL of solution water is added and volume was changed to 250 mL.
So, volume of the final solution = 250 mL = 0.250 L (1 mL = 0.001 L)


The concentration of the solution is 1.364 molar.
The daughter isotope (a decay product)of O-15 = N-15(Nitrogen 15)
<h3>Further explanation
</h3>
Radioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles,
- alpha α particles ₂He⁴
- beta β ₋₁e⁰ particles
- gamma particles γ
- positron particles ₁e⁰
O-15 emits positron particles ₁e⁰, so the atomic number decreases by 1, the mass number is the same
Reaction

The mass number of the daughter isotope = 15, atomic number = 7
If we look at the periodic system, the element with atomic number 7 is Nitrogen (N)
Answer:
The weigth of a 90kg man standing on the moon is <u><em>147.6 N (option C)</em></u>
Explanation:
Weight is called the action exerted by the force of gravity on the body.
The mass (amount of matter that a body contains) of an object will always be the same, regardless of where it is located. Instead, the weight of the object will vary according to the force of gravity acting on it.
The formula that allows you to calculate the weight of any body is:
W = m*g
where:
- W = weight measured in N.
- m = mass measured in kg.
- g = acceleration of gravity measured in m/s². The acceleration of gravity g is the same for all objects that fall due to gravitational attraction, whatever their size or composition. For example, as an approximate value on Earth, g = 9.8 m/s².
In this case, the mass m has a value of 90 kg and the gravity g has a value of 1.64 m/s², which is the value of the acceleration of gravity of the moon. Then:
W=90 kg* 1.64 m/s²
<u><em>W= 147.6 N</em></u>
Finally, <u><em>the weigth of a 90kg man standing on the moon is 147.6 N (option C)</em></u>
Solar, or <span>radiant to chemical.</span>
Answer:
D:Nuclear fusion plays an important role in making elements that are heavier than helium
Explanation:
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