Specific heat is the quantity of heat required to change the temperature of 1 gram of a substance by 1 degree Celsius. It is the amount per unit mass that is required to raise the temperature by one degree Celsius. Every substance has its own specific heat and each has its own distinct value. The units of specific heat are joules per gram-degree Celsius (J/f C) and sometimes J/Kg K may also be used.
Explanation:
Because when two equal forces are applied from opposite directions, they "eliminate" each other.
The train would go right if a 3N force was only applied in the right direction, and it would go left if the same force was only applied to the left.
If a 3N force was applied to the right and a 2N force to the left, it would equal a 1N force to the right (3-2=1).
But there it's 3-3=0, so in practice the force is 0N. Therefore the train won't move.
First, we must know what happens in the precipitation reaction. This type of reaction is a double replacement reactions. It is consists of two reactant compounds which interchange cations and anions to form two products. One of the products is an insoluble solid called a precipitate. For the precipitation of CaCO₃, there are two consecutive reactions involved:
1. Slaking of quicklime, CaO
CaO + H₂O ⇒ Ca(OH)₂
2. Precipitation
Ca(OH)₂ + CO₂ ⇒ CaCO₃ + H₂O
The ions that make up the H₂O molecule are H⁺ and OH⁻. According to solubility rules, the cation (positively charged ion) is likely to be attracted to an anion (negatively charged ion). Together, they form an ionic bond. This type of bond is when there is a complete transfer of electrons between the two. The Ca²⁺ cation lacks 2 electrons, while the anion OH⁻ has an excess 1 electron. In order to be stable, 1 Ca²⁺ ion and 2 OH⁻ ions must combine.
Therefore, the answer is OH⁻ ion.