Answer:
It was built to house the employees of the Chernobyl Nuclear Power Plants located 4 kilometers away and became the ninth nuclear city in the Soviet Union.
Explanation:
Correct Question:
A chemist measures the enthalpy change ΔH during the following reaction: Fe(s) + 2HCl(g)-->FeCl2(s) + H2 ΔH=-157.0 kJ. Use this information to complete the table below. Round each of your answers to the nearest kJ/mol
Answer:
-314 kJ
+628 kJ
+157 kJ
Explanation:
The enthalpy change of a reaction measures the amount of heat that is lost or gained by it. If ΔH >0 the heat is gained, and the reaction is called endothermic, if ΔH<0, the heat is lost, and the reaction is called exothermic.
If the reaction is inverted, the value of ΔH is inverted too (the opposite endothermic reaction is exothermic), and if the reaction is multiplied by a constant, ΔH will be multiplied by it too.
1) 2Fe(s) + 4HCl --> 2FeCl2(s) + 2H2(g)
This reaction is the product of the given reaction by 2, so
ΔH = 2*(-157) = -314 kJ
2) 4FeCl2(s) + 4H2(g) --> 4Fe(s) + 8HCl(g)
This reaction is the inverted reaction given multiplied by 4, so
ΔH = 4*(157) = +628 kJ
3) FeCl2(s) + H2(g) --> Fe(s) + 2HCl
This reaction is the inverted reaction given, so
ΔH = +157 kJ
Answer:
B. an element
Explanation:
An atom is smallest indivisible particle that takes part in a chemical reaction. Different atoms due to the number of their protons called atomic number gives an element. Every element is a singular atom on it's own. Combination of atoms leads to the formation of molecules and compounds.
When compounds mix together without an actual chemical change, a mixture forms.
Elements are distinct substances that cannot be split up into simpler substances. They are usually made up of only one kind of atom.
Answer:

Explanation:
The Celsius and Kelvin scales are used to measure the temperature of matter. Their scales and unit differences are the same (1 K increase = 1 °C increase), but they have different starting points.
So, the conversion is quite simple and only requires addition because of the different starting points. The formula is:

The boiling point of liquid nitrogen is -195.8 °C. We can substitute this value into the formula.


The boiling point of liquid nitrogen is 77.35 Kelvin.