The answer is true the si base unit for mass is the gram
This means a release of free energy from the system corresponds to a negative change in free energy, but to a positive change for the surroundings.
Answer:
The answer to your question is 1.1 moles of water
Explanation:
2Al(OH)₃ + 3H₂SO₄ ⇒ Al₂(SO₄)₃ + 6H₂O
0.45 mol 0.55 mol ?
Process
1.- Calculate the limiting reactant
Theoretical proportion
Al(OH)₃ / H₂SO₄ = 2/3 = 0.667
Experimental proportion
Al(OH)₃ / H₂SO₄ = 0.45 / 0.55 = 0.81
From the proportions, we conclude that the limiting reactant is H₂SO₄
2.- Calculate the moles of H₂O
3 moles of H₂SO₄ ---------------- 6 moles of water
0.55 moles of H₂SO₄ ----------- x
x = (0.55 x 6) / 3
x = 3.3 / 3
x = 1.1 moles of water
Iodine has an electronegativity of 2.5, and potassium has an electronegativity of 0.8, so the difference is:
2.5 - 0.8 = 1.7
Answer:
magnesium metal melts = physical change
magnesium metal ignites = chemical change
Explanation:
<em>Physical changes</em> are those in which the identity of the subtance <u>remains unaltered</u>. No new compounds are formed. They involve generally changes in <u>agreggation states of matter</u>: solid, liquid or gas. The first experiment, in which magnesium metal melts is a physical change because it only changes the state of matter, from solid to liquid, but it is still magnesium metal.
Conversely, <em>chemical changes</em> involve atoms combinations to form new compounds. The second experiment, in which magnesium metal ignites, is a chemical change. After the change, magnesium metal is no longer the metal but a metal oxide.
