Answer:
The chemical change in matter is results in a change in its identity and properties.
Explanation:
There are toe type of changes physical change and chemical change.
The chemical change change in matter lead to lost its identity and properties.
Chemical change:
The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.
These changes are irreversible
These changes occur due to chemical reactions
These may not be observed with naked eye
Example:
Combustion of fuel or wood: that oil or wood convert into energy, CO2 and ash in case of wood
Boiling of egg: that change the chemical composition of protein in the egg .
The reaction of Hydrogen and oxygen:
H 2 (g) + O 2 (g) -------------------------------------> 2H 2O (l)
Answer:
The answer to your question is below
Explanation:
Metals lose electrons and Nonmetals gain them.
a. Ra is in group IIA it will lose electrons, the ion will be Ra⁺²
b. Br is in group VIIA it will gain electrons, the ion will be Br⁻¹
c. In is in group IIIA it will lose electrons, the ion will be In⁺³
d. Te is in group VIA it will gain electrons, the ion will be Te⁻²
e. Ca is in group IIA it will lose electrons, the ion will be Ca⁺²
f. As is in group VA it will gain electrons, the ion will be As⁻³
g. Al is in group IIlA it will lose electrons, the ion will be Al⁺³
h. Rb is in group IA it will lose electrons, the ion will be Rb⁺¹
1 mole of any substance contains Avogadro's number.
So, 1 mole of O2= 6.023x10^23 molecules
3 mole of O2= 6.023x10^23x3 molecules
= 1.8069x10^24 molecules
Each molecule of Oxygen has 2 atoms.
therefore,
1.8069x10^24 molecules= 1.8069x10^24 x 2 atoms
= 3.6138x10^24 atoms.
Explanation:
Hi for this one u just need to remember and use the equation.
then u find mr of potassium which is 39.1.
then u do
you get the answer as 0.5115 write ur answer to 3 significant figures which will be 0.512 moles .
hope this helps :)
