There are 6 neutrons in an atom of Boron
The criteria are that the desk must:
- Be no more than 40 in wide
- Have at least one drawer
Answer:
V₁ = 208.3 mL
Explanation:
Given data:
Initial molarity of HCl = 6.0 M
Final volume = 500 mL
Final molarity = 2.5 M
Volume of initial solution required = ?
Solution:
Formula:
M₁V₁ = M₂V₂
Now we will put the values in formula.
6.0 M × V₁ = 2.5 M ×500 mL
6.0 M × V₁ = 1250 M.mL
V₁ = 1250 M.mL / 6.0 M
V₁ = 208.3 mL
<span>Answer: option C) pure substance.
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<span>Justification:
</span><span />
<span>A sharp melting point is a characteristic of pure substances.
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<span>The pure substances are either elements or compounds: they have a unique chemical constitution (kind of elements, number of atoms of each element in the chemical formula, and same chemical bonds).
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</span><span> Other products, this is mixtures (either homogeneus or heterogeneous), being composed of different elements and compounds in different variable ratios, exhibit a range as boiling point. For example the boiling point of the gasoline is about 19°C to 200°C.
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Bromine is an element: you find it in the periodic table, with the atomic number 35, hence a pure substance.
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Answer: D)The distance from Earth and mass of ISS exert negligible gravitational force on the astronaut.
Explanation:
The distance from Earth and mass of ISS exert negligible gravitational force on the astronaut. Gravity is a very weak force and varies with mass and the inverse square of distance. The astronaut's distance from Earth and the relative small mass of ISS result in gravitational force near zero.