Answer: Because new substances are formed.
Explanation: A chemical property is any of a material's properties that becomes evident during, or after, a chemical reaction; that is, any quality that can be established only by changing a substance's chemical identity. Once a chemical change occurs it cannot be undone due to the change in chemical identity. The creation of a new substance is not reversible.
Answer:
Calcium (Ca²⁺)
Explanation:
Calcium is very important mineral, found in teeth and bones primarily.
It is needed for the strong bones.
It is very important to maintain the bones in order to support our skeleton.
In our body it is also important to carry out other functions like in muscles, nerve function and also for heart.
If our diet is not full of calcium, the calcium deficiency may occur which leads to the weakening of bones and cause fracture.
The dietary source of calcium includes:
Yogurt, cheese, milk
beans such as peas, peanuts.
fishes
almonds, oranges, molasses
Answer:
The piece of wood will sink
Explanation:
If an object has a density higher than water, it will sink, and the piece of wood is more dense than water when measured.
Answer:
10°C
Explanation:
Heat gain by water = Heat lost by the slice of pizza
Thus,

<u>For water: </u>
Volume = 50.0 L
Density of water= 1 kg/L
So, mass of the water:
Mass of water = 50 kg
Specific heat of water = 1 kcal/kg°C
ΔT = ?
For slice of pizza:
Q = 500 kcal
So,
ΔT = 10°C
Increase in temperature = 10°C
Most atoms have three different subatomic particles inside them: protons, neutrons, and electrons. The protons and neutrons are packed together into the center of the atom(which is called the nucleus) and the electrons, which are very much smaller, whizz around the outside. Most of an atom is empty space.
I hope this helps you! :D