The phase change H₂(g) → H₂(s) is called deposition, and the enthalpy change, ΔH, for this phase change has a negative (-) sign.
Deposition<span> is a </span>thermodynamic process<span> in which </span>gas<span> transforms into </span>solid<span> without passing through the </span>liquid phase<span>. Example is formin snow in clouds directly from water vapor. In deposition energy is released.</span>
Answer:
8.31 × 10⁻²² kJ
Explanation:
Step 1: Given data
Energy required to remove one mole of electrons from the atoms at the surface of a solid metal: 500 kJ/mol e⁻
Step 2: Calculate how much energy does it take to remove a single electron from an atom at the surface of this solid metal
We will use Avogadro's number: there are 6.02 × 10²³ electrons in 1 mole of electrons.
500 kJ/mol e⁻ × 1 mol e⁻/6.02 × 10²³ e⁻ = 8.31 × 10⁻²² kJ/e⁻
Answer:
D
Explanation:
The force of gravity depends directly upon the masses of the two objects, and inversely on the square of the distance between them. This means that the force of gravity increases with mass, but decreases with increasing distance between objects.
The chain reaction is easy to stop. Just add a neuron absorbing material. The Control Rods in rectors can do that You just SCRAM (put the rods all the way in) or add something like Boron and the chain reaction stops.
<span>The problem is the radioactive waste. Those isotopes break down and release heat spontaneously, no neutrons required. The only known way to stop or slow radioactive decay down is to slow time down by moving at relativistic speed or near orbit to a black hole.</span>
1. Double-Replacement reactions
2. Decomposition
3. Combustion
4. Syntesis
5. Single replacement
<h3>Further explanation</h3>
Given
Chemical equations
Required
Type of reaction
Solution
1. 2AgNO₃ + MgCl₂ ⇒ 2AgCl + Mg(NO₃)₂
Double-Replacement reactions. Happens if there is an ion exchange between two ion compounds in the reactant
2. 2KBr⇒2K +Br₂
Decomposition
Single compound breaks down in to 2 or more products
3. C₃H₈ + 5O₂ ⇒ 4H₂O + 3CO₂
Combustion
Hydrocarbon and Oxygen reaction and form water and carbon dioxide
4. NaO + H₂O ⇒ NaOH
Syntesis
2 or more reactants combine to form a single product
5. Zn + CuCl₂ ⇒ZnCl₂ + Cu
Single replacement
One element replaces another element from a compound