Answer:
C) exothermic
Explanation:
The given reaction is exothermic.
N₂ + 3H₂ → 2NH₃ + ENERGY
when energy is released the reaction is exothermic and when energy is written on left side with reactant it means energy is added and reaction is endothermic.
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
Answer: 1.67 kg
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.
Q = Heat absorbed=
= 
(1kJ=1000J)
m= mass of substance = ?
c = specific heat capacity = 
Change in temperature ,
Putting in the values, we get:
(1kg=1000g)
Thus the mass (in kg) of the copper sample is 1.67
Answer: A. Is decomposition
B. Is synthesis where Na combines with Cl to form NaCl
C. Is single displacement or replacement. Mg displaces Cu.
Explanation:
Answer:
V₂ = 2.91 L
Explanation:
Given data:
Initial volume = 3.50 L
Initial temperature = 90.0°C (90+273 = 363 K)
Final temperature = 30.0 °C ( 30 +273 = 303 K)
Final volume = ?
Solution:
V₁ = Initial volume
T₁ = Initial temperature
V₂ = Final volume
T₂ = Final temperature
V₁/T₁ = V₂/T₂
3.50 L / 363 K) = V₂ / 303 K)
V₂ = 0.0096 L/K × 303 K
V₂ = 2.91 L
Answer:
The cubic centimeter of boron is 2.
Explanation:
Density:
Density is equal to the mass of substance divided by its volume.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
Symbol:
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
Given data:
mass of boron = 4.68 g
density of boron = 2.34 g/cm³
volume = ? (cm³)
Solution:
d = m/ v
v = m/d
v = 4.68 g/ 2.34 g /cm³
v = 2 cm³
