The question is incomplete but i will try to offer as much help as i can.
Answer:
See explanation
Explanation:
The electron was discovered by J.J Thompson. His model of the atom was called the plum-pudding model of the atom.
He discovered that cathode rays being negatively charged particles were deflected by a magnet in just the same way as moving, negative electrically charged particles.
Similarly, in an electric field, they are deflected towards the positive plate of the electrostatic field which shows that they are negatively charged.
If you were to cut the radium in half and have only 90 g, it will take up 18 cm³.
<h3>
What is density?</h3>
The density of an object is the ratio of mass to volume of object.
Density = mass/volume
volume = mass/density
at a constant density, the volume of an object is proportional to its mass.
From the question, you have 180 g of radium that takes up 36 cm ^ 3 of space if you were to cut it in half and have only 90 g, the new mass will take the following volume.
180 g = 36 cm³
90 g = ?
= (90 x 36) / 180
= 18 cm³
Thus, if you were to cut the radium in half and have only 90 g, it will take up 18 cm³.
Learn more about radium here: brainly.com/question/23781489
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It is <u>true</u> that ionic compounds are formed from atoms that have opposite charges.
<h3>What are ionic compounds?</h3>
Ionic compounds are chemical compounds made up of ions held together by electrostatic forces termed ionic bonding.
The ionic compound formed is neutrally charged but consists of positively charged ions called cations and negatively charged ions called anions.
For example, the sodium ions attract chloride ions and the chloride ion attracts sodium ions. The result is the formation of an ionic compound with cation Na+ and anion Cl– ions.
Therefore, it is true that an ionic compound is made up of positive and negative ions.
Learn more about ionic compound at: brainly.com/question/9167977
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it's B Cell wall
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Answer:Explanation:Protons and other subatomic particles will be discussed a little later. The atoms of different elements are different from each other because they have different numbers of protons. The graphic below illustrates this point by showing the atoms of two elements in the containers of oxygen and hydrogen.
