Answer:
a) 128 grams
b) 81.25%
Explanation:
a) The mixture will be between the alloy and the pure copper, so the mass will be the sum of the mass of the compounds:
m = 50 + 78 = 128 g
b) In the alloy, 52% is copper, so to know the mass of copper in the alloy, we must multiply the total mass by 52% (which is 0.52)
0.52x50 = 26 g of copper
The total mass of copper in the mixture is 26 + 78 = 104 g
So, the percentual of copper is the mass of copper divided by the total mass
104/128 = 0.8125
Multiplying by 100%, to have the result in percentage
0.8125x100% = 81.25%
Answer: 2 Ag3N => 6 Ag + N2
Explanation: Decomposition is expressed through this generic equation:
AX => A+ X
After the reaction balance the chemical reaction.
Always remember that a compound can be separated into simpler substances by chemical methods/reactions. While elements cannot be broken down into simpler substances by chemical reactions. You can do a flame test and spectrum analysis to determine whether a solid material is an element or a compound. Check the boiling and/or melting point, color or density. Also check the solid material’s reaction with oxygen, hydrogen, calcium, or various acids. Examine and study its physical chemistry. The element(s) that may be present may be identified by checking the absorption edges from an x-ray spectrum.
For instance, a solid white material (A) is heated in the absence of air, decomposing to form a new white material (B) and gas (C). Gas (C) has the same properties as the products when carbon is burned in an excess of oxygen (CO2). How can we determine whether A, B, and C are elements or compounds? A would be a compound since it was broken down into B and C. So how do we determine B and C?
A compound can be decomposed, for the reason that a compound is composed of 2 or more elements. On the contrary, an element cannot be decomposed.
Answer:
a. 52.8
Explanation:
To find the number of moles of HCl we use the relation M₁V₁=M₂V₂
where M₁ is the initial molarity, M₂ the new molarity, V₁ the initial volume used, and V₂ the final volume obtained.
M₁=7.91 M
M₂=2.13 M
V₁=?
V₂=196.1 mL
Replacing these values in the relationship.
M₁V₁=M₂V₂
7.91 M× V₁=2.13 M×196.1 mL
V₁=(2.13 M×196.1 mL)/7.91 M
=52.8 mL
The mass number of an atom is basically the total number of protons and neutrons.
