Answer:
The answer to your question is: letter A
Explanation:
We can find carbon and hydrogen in the periodic table of the elements then, they are elements. Elements are composed by only one kind of atoms.
We can not find methane in the periodic table so, Methane is a compound. Compounds are composed by 2 or more atoms of the same element or of different elements.
Letter B is incorrect because carbon and hydrogen are elements.
Letter C is incorrect because Methane is a compound and carbon and hydrogen are elements.
Letter D is incorrect because Methane is a compound.
Answer:
The answer to your question is: KNO₃
Explanation:
AgNO3 + KCl → AgCl + −−−−
A. KNO3 this option is correct because it is a double replacement reaction then potassium must attached to NO₃.
B. KOH this product is not possible because there is no water to form OH⁻ ions.
C. Ag2K this product is not possible because both Ag and K are metals, then it is difficult that they attach.
D. KN2O This product is imposible to form, this option is wrong.
Answer
Energy = 3135 J
Explanation
<em>Given:</em>
Mass of water = 12.5 g
Final temperature = 72 C
Initial temperature = 12 C
Specific heat of water = 4.18 J/g C
<em>Required:</em> Energy
Solution
Q = m x Cp x ΔT
where Q is heat absorbed or released
m is the mass
Cp is the specific heat capacity
ΔT = final temperature - initial temperature
Q = 12.5 g x 4.18 J/gC x (72 - 12 C)
Q = 3135 J
Answer:
28/44*100%=63.6%
Explanation:
the gram formula mass of N20 is 14*2+16=44.The mass of two nitrogen atom is 14*2=28,so the percentage is that 28/44*100%=63.6%.
