Answer:
Non metals join to form covalent bond.
Explanation:
Covalent bond:
It is formed by the sharing of electron pair between bonded atoms.
The atom with larger electronegativity attract the electron pair more towards it self and becomes partial negative while the other atom becomes partial positive.
For example:
In water the electronegativity of oxygen is 3.44 and hydrogen is 2.2. That's why electron pair attracted more towards oxygen, thus oxygen becomes partial negative and hydrogen becomes partial positive.
Both atoms bonded through covalent bond.
In Cl₂ both chlorine atoms are bonded through the covalent bond.
Iron has the chemical formula Fe from its Latin name, ferrum. Its atomic number is 26, and its molar mass is 55.845 grams per mole. It has a metallic gray color and is attracted to magnets. Iron is the second most-abundant metal on Earth.
Answer : The mass in grams of calcium sulfate is 0.16 grams.
Explanation :
Molarity : It is defined as the number of moles of solute present in one litre of solution.
Formula used :
Solute is, 
Given:
Molarity of = 0.0025 mol/L
Molar mass of = 136 g/mole
Volume of solution = 485 mL
Now put all the given values in the above formula, we get:
Thus, the mass in grams of calcium sulfate is 0.16 grams.
The best answer among the choices given is option A. Chemical weathering of rocks is a source of dissolved substances in the ocean. It is a process that involves the erosion of rocks due to chemical reactions by water and substances dissolved in the water. Therefore, it most likely the source of dissolved substances.
