The items that are true of early nuclear science are "the first nuclear reactions were done in the 1880s" and "the first nucleus split was uranium-235." <span>The answers are letters A and D. It is impossible that nucleus was lost during the reaction as it will not follow the law of mass conservation.
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Answer:
Float
Explanation:
If the weight of liquid displaced and the weight of an object are the same, the object will float in the liquid.
From Archimedes principle, when an object is immersed in fluid, a force called upthrust supports it and it equal to the weight of the liquid displaced.
When in a liquid, the weight of the liquid displaced is the same as that of the of the object, it will float and not sink.
Answer:
0.175mol
Explanation:
Mole of a substance can be calculated using the formula as follows:
number of moles (n) = mass (m) ÷ molar mass (MM)
According to this question, there are 4.2g of Magnesium (Mg).
Molar mass of Magnesium = 24g/mol, hence, the number of moles of 4.2g of Mg is as follows:
n = 4.2g ÷ 24g/mol
n = 0.175mol
7 strong acids are strong electrolytesHCl, HBr, HI, HNO3, HCIO3, HCIO4, and H2SO4
3 strong bases are strong electrolytes<span>OH, KOH, and NaOH</span>
Answer:
Mass = 12.276 g
Explanation:
Given data:
Number of molecules of H₂S = 2.16 × 10²³
Mass in gram = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
Number of moles of H₂S:
2.16 × 10²³ molecules × 1 mole /6.022 × 10²³ molecules
0.36 moles
Mass = number of moles × molar mass
Mass = 0.36 mol × 34.1 g/mol
Mass = 12.276 g
