Answer:
The correct answer is - hard water reacts to form the calcium or magnesium salt of the organic acid of the soap.
Explanation:
Soaps are made up of fatty acids or oils by treating with strong alkali and are salts of sodium and potassium. Hard water, on the other hand, has a high concentration of minerals in comparison to soft water. When hard water and soap are mixed together the salts of the minerals like Ca2+ and Mg2+ ions present in hard water react with fatty acids of the soap.
The sodium salts are changed to the salts of calcium and magnesium which are precipitated to an insoluble substance. The insoluble salts of the calcium or magnesium dirt stick on the clothes thus cleaning ability of soap is reduced.
Answer:
Helium
Explanation:
Helium is most likely to undergo a chemical reaction because
- It has a complete electron shell, so it does not need any more electrons
- Its electrons are closest to the nucleus, so it is extremely difficult to remove them
Answer:
Energy in an ecosystem comes from the Sun.
Explanation:
It is a major source of energy for organisms, plants and the whole ecosystem basically.
Answer:
B. gas state at room temperature
Explanation:
Answer:
1.67g/cm3
Explanation:
The formula for density is 
. The m variable stands for mass and the v variable stands for volume.
The mass of the brown sugar is 10.0g and the volume is 6.0cm3, so we can plug those values into the equation.
Rounded to 3 significant figures, the density of the block of brown sugar is 1.67 g/cm3. If the mass is in grams and the volume is in cm3, the unit for the final answer is (grams per centimetres cubed).
