Isotopes are atoms of the same element that differ in the number of neutrons.
Remember that all the atoms of an element have the same number of protons. So the only difference between isotopes of an element is the number of neutrons.
86 Sr means that the mass number of this isotope is 86. Also, remember that the mass number is the number of protons plus the number of neutrons.
87 Sr means that the mass number of this isotope is 87.
So, 86 Sr and 87 Sr differ 1 neutron.
Answer: 1 neutron
No. The number of a protons is not equal to it's atomic weight, instead it is equal to the 'atomic number'
The answer is:
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The principal thing that one can read from a periodic table is the atomic number which is the number in the box that the element symbol appears and it means the number of protons in the nucleus of its atom and this number determines its chemical properties and is unique for each chemical element. The table is color coded to show the different types of elements ie "transition metals, alkali metals, noble gases" etc. and these different types are grouped together.
The temperature at which phase changes occur is highly dependent on the electrostatic forces between the molecules in the substance.
The forces that hold molecules together are called intermolecular forces. These intermolecular forces affect the temperature at which phase changes occur. The statement about phase changes and electrostatic forces that is correct is that; "the temperatures at which a substance changes phases indicate the relative strength of the forces between molecules in the substance."
There are three states of matter, solid liquid and gas. The order of intermolecular forces in all the states of matter are not the same. The order of strongest collective electrostatic forces to weakest collective electrostatic forces is; solid, liquid, gas.
When water boils, the forces between water molecules break, and the bonds between the atoms in water are unchanged.
When a sample of calcium carbonate is cooled, the forces strengthen, and the molecule structure becomes more rigid.
If the boiling point of acetone is lower than the boiling point of ethanol, then, the intermolecular forces in ethanol are stronger than the intermolecular forces in acetone.
Learn more about phase changes: brainly.com/question/671212
