Answer: -
2.5 moles of calcium atoms are in 2.5 moles of calcium carbonate CaCO₃
Explanation: -
In order to solve such types of problems, the first step would be to write the chemical formula of the compound.
The chemical formula of calcium carbonate = CaCO₃
The chemical symbol of Calcium is Ca.
From the formula of calcium carbonate we can see that
1 mole of CaCO₃ has 1 mole of Ca
2.5 mole of CaCO₃ has 
= 2.5 mol of Ca.
∴2.5 moles of calcium atoms are in 2.5 moles of calcium carbonate CaCO₃
Tobacco juice would be your correct answer.
Answer: The bond formed between magnesium and oxygen is an ionic bond.
Explanation:
An ionic bond is formed when an atom transfer its valence electrons to another atom.
Whereas, a covalent bond is formed by the sharing of electrons between the atoms.
Silicon and oxygen forms silicon dioxide. Silicon has 4 valence electrons which are shared with each oxygen atom. Hence, silicon and oxygen forms a covalent bond.
Oxygen and oxygen shares two pairs of electrons therefore, a covalent bond is formed between oxygen and oxygen.
A covalent bond is formed between carbon and hydrogen as carbon has 4 valence electrons which are shared with four hydrogen atoms.
Magnesium has 2 valence electrons which are transferred to the oxygen atom in order to complete its octet.
Therefore, the bond formed between magnesium and oxygen is an ionic bond.
Answer:
Atoms of matter are electrically neutral because their nuclei contain the same number of protons as there are electrons surrounding the nuclei. Electric current and charged objects involve the separation of some of the negative charge of neutral atoms.
