Answer:
A. It is exothermic
Explanation:
Combustion is a chemical reaction in which a substance combines with oxygen present in air to produce carbon (iv) oxide and water as well release heat and light energy.Combustion is an exothermic process.
An exothermic reaction releases energy in the form of heat to the surroundings. The energy required to break bonds in the reactants is less than the energy required to form new bonds in the products in an exothermic reaction.
From the given options;
A. It is exothermic is determinable since the reaction is a combustion reaction
B. The bond making energy is more than 600 kJ is not certain because the mass of the wood being burnt is not given. Also, wood is not composed of a specific element that would be taking part in the reaction, rather it is composed of various substances.
C. It is endothermic. is wrong because combustion of wood is exothermic.
D. The bond breaking energy is more than 600 kJ is not certain because the mass of the wood being burnt is not given. Also, wood is not composed of a specific element that would be taking part in the reaction, rather is composed of many substances.
Bromine. This is because they are in the same grp. Elements in the same grp have similar chemical properties.
Answer:
Only reaction 1
Explanation:
C + O2 → CO
the charge of C in CO is +2 (oxidation)
from 0 to +2
the charge of O in CO is -2 (reduction)
from 0 fo -2
Hence it is a redox (reduction-oxidation) reaction
This is also valid for,
C + O2 → CO2
the charge of C in CO2 is +4 (oxidation)
charge increases from 0 to +4
the charge of O in CO2 is -2 (reduction)
charge decreases from 0 to -2
hence, it is a redox reaction
K2SO4 + CaCl → KCl + CaSO4
none of the charges changes in this reaction
please recheck, for this may not be the correct answer
maybe give brainliest
Answer:Option B) 63.55 amu
Explanation:To find the average atomic weight of the two isotopes of copper that exist in nature we can use the below formula;
Average atomic mass = ∑ (isotope(s) x abundance)
Therefore, we have the given values of atomic masses of two copper isotopes are 62.93 u and 64.93 u, respectively. They have natural abundance as 0.692 and 0.368, respectively,
On substituting the above values, we get,
Average atomic mass = (62.93 x 0.692) isotope 1 of Cu + (64.93 x 0.308) isotope 2 of Cu
Average atomic mass = 43.54 + 19.99 = 63.538 ~ 63.55
Therefore, the average atomic mass of Cu will be 63.55 amu.
You can infer that the different elements have different light spectrum frequencies, causing the different light colors.