1) Solids have a fixed shape
The particles of solids are held into their positions and are only able to vibrate about fixed points. The strength of the bonding means that the particles have their own shape, which they retain, and do not take the form of the container they are in.
2) Solids may not flow
The molecules of liquids are able to slide past one another due to weaker bonds between particles. This allows the liquid to flow; whereas, this movement is not possible in solids so they cannot flow.
3) Solids may fracture
The fact that solids possess a rigid structure means that they have the ability to fracture. Although some are able to withstand more stress than others, all solids may break. This breakage occurs when the intermolecular bonds are mechanically broken. This is not possible in the case of liquids because such rigid intermolecular bonds do not exist.
Its B and D
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Answer:
The correct answer is - alpha particle and positron.
Explanation:
In this question, it is given that, 38^88Sr decays to 34^84Kr, which means there is an atomic number decrease by 4, 38 to 34, and atomic mass decreases by 4 as well 88 to 84.
A decrease in the atomic mass is possible only when there is an emission of the alpha particle as an alpha particle is made of 2 protons and 2 neutrons. If an atom emits an alpha particle, there is a change in atomic number as it decreases by two, and its mass number decreases by four.
So after the emission of an alpha particle, the new atom would be
38^88Sr=> 36^84X => 34^84Kr
so there is also two positron emission that leads to decrease in atomic number by one with each emission:
38^88Sr=> 2^4He+ 36^84X => 36^84X + 2(1^0β+) => 34^84Kr
Positron decay is the conversion of a proton into a neutron with the emission of a positron that causes the atomic number is decreased by one, which causes a change in the elemental identity of the daughter isotope.
Answer:the answer is hypothesis
Explanation: that’s the answer
