Answer:the term 'atom' in chemistry represents the basic unit of matter that normally exists in a free state and contains all chemical properties. It is an infinite particle that clearly identifies a chemical element. It consists of a positively charged nucleus and is surrounded by negatively charged electrons.
An ion or charge is an atom or group of atoms that has lost or gained one or more electrons. An ion that has a negative charge, when it gains one or more electrons, is called an anion or negative charge, and an ion that has a positive charge when it loses one or more electrons, is called a cation or positive charge.
Explanation:
Answer: A substance that produces hydroxide ions when placed in water is base.
Explanation:
Bases are the substance:
- Which gives negatively charged hydroxide(
) ions in aqueous solution.
- Which have pH value ranging from 7 to 14.
Where as acid gives positively charged hydronium ion(
) in aqueous solution.
Hey there!:
Number of moles:
Molar Mass Al = 26.98 g/mol
n = mass / molar mass
n = 9.0 / 26.98
n = 0.3336 moles of Al
Given the reaction :
2 Al + Fe2O3 = Al2O3 + 2 Fe
From the equation, 2 moles of Al give off 849 kJ of heat :
Actual heat given off :
0.3336 / 2 * 849 =
0.3336 / 1698 = 1.4*10² Kj
Hope that helps!
