<h2>Which of the following reactions is endothermic-</h2><h2>½N2(g) + O2(g) + 8.1 kcal → NO2(g)</h2>
Explanation:
Chemical reaction
When two or more substances react and form some new substance it is called as chemical reaction .
A + B --> C + D
(reactants ) (products )
When ever chemical reaction occurs following changes can occur :
- Change in colour
- Ppt formation
- energy changes
- Change in state
- Evolution of gas etc
On the basis of energy changes : reactions are of two types :
Endothermic
Exothermic
Endothermic reaction
A reaction in which heat is absorbed .
Example :½N2(g) + O2(g) + 8.1 kcal → NO2(g)
Exothermic reaction
A reaction in which heat is released .
For example : H2(g) + ½O2(g) → H2O(g), ΔH = -57.82 kcal
½N2(g) + 3/2H2(g) → NH3(g) + 11.0 kcal
C(diamond) + O2(g) → CO2, ΔH = -94.50 kcal
Answer:
protists that produce a hard outer covering have left many fossils, other protists lack hard parts, so few fossils of these organisms have been found. ... Protists in this group are called plantlike because, like plants, they contain the pigment chlorophyll in chloroplasts and can make their own food.
Explanation:
Hope it helps, some how.
Answer:
Answer. K2CO3 = 138 g/mol.
FORCE is how strongly gravity pulls on an object
MASS measures how much space matter takes up
Hope that helped! Good luck!
Answer:
Vapour pressure of liquid is affected by its TEMPERATURE, TYPE OF LIQUID, ADDITION OF SOLUTES.
Explanation:
Vapor pressure is the pressure exerted by a vapor in equilibrium with its liquid. Mathematically, the vapor pressure of liquid is written as:
In (Pvap) = -ΔHvap / R * (1/T) + C
ΔHvap is the enthalpy of vaporization and it is constant for specific liquid, T is the temperature and C is a constant. Temperature therefore affect the vapor pressure of a liquid as increase in temperature can cause an increase in vapor pressure.
The type of liquid also affect the vapor pressure. If the molecules bind to each other strongly in the liquid, it increases vapor pressure to be exerted by the liquid but if the type of liquid is one with weak forces of attraction, the vapor pressure is reduced.
Addition of solute to the liquid increases the boiling temperature of liquids thereby reducing it's vapor pressure.
