Sound energy is produced when an object vibrates. The sound vibrations cause waves of pressure that travel through a medium, such as air, water, wood or metal. Sound energy is a form of mechanical energy. (I believe this is it)
Answer:
0.39760273
Explanation:
I typed into calculator hope it's right.
The answer is: 27 grams of aluminium.
Balanced chemical reaction: 2Al + 3H₂SO₄ → Al₂(SO₄)₃ + 3H₂.
n(H₂) = 1.5 mol; amount of hydrogen.
Form chemical reaction: n(Al) : n(H₂) = 2 : 3.
n(Al) = 2 · 1.5 mol ÷ 3.
n(Al) = 1.0 mol; amount of aluminium.
m(Al) = n(Al) · M(Al).
m(Al) = 1 mol · 27 g/mol.
m(Al) = 27 g; mass of aluminium.
Answer:
NH4Cl, NaCl, Ba(OH)2, NaOH
Explanation:
NH4Cl is an acidic salt formed by the neutralization of a strong acid (HCl) with a weak base (NH3). Hence, it will habe a PH<7 (the lowest PH).
NaCl is a neutral salt,formed by neutralization of a strong acid (HCl) with a strong base (NaOH). Hence, it will have a PH of 7.
Ba(OH)2 is a weak base. Therefore, it will have a PH between 8 and 10.
NaOh meanwhile, is a strong base. Therefore, it will have a PH between 10 to 13.
Hence, we have
NH4Cl < NaCl < Ba(OH)2 < NaOH