The correct option is B. The alkali metals combine directly with halogens forming high melting point crystalline solids that have high negative enthalpies of formation. The entalphy of formation for lithium bromide is the highest and the values decrease down the group, thus, lithium is the most stable while cesium is the least stable.
Answer:
The answer to your question is 900 g of water vapor
Explanation:
Data
mass of H₂O = ?
mass of butane = 580 g
Balanced chemical reaction
2C₄H₁₀ + 13O₂ ⇒ 8CO₂ + 10H₂O
Process
1.- Calculate the molar weight of butane and water
Butane (C₄H₁₀) = 2[(12 x 4) + (1 x 10)]
= 2[48 + 10]
= 2[58]
= 116 g
Water (H₂O) = 10[(1 x 2) + (1 x 16)]
= 10[2 + 16]
= 10[18]
= 180 g
2.- Use proportions and cross multiplication to find the mass of water vapor
116 g of butane ------------- 180 g of water
580 g of butane ---------- x
x = (580 x 180) / 116
x = 900 g of water vapor
It is either the 3rd answer or the 4th answer. Both are correct ways to write hydrates, but I was taught the 4th way. Just make sure this answer matches the format of the examples your teacher gave you.
For a hydrocarbon, the combustion reactions are the following:
C + O₂ --> CO₂
H₂ + 1/2 O₂ --> H₂O
The molar mass of CO₂ is 44 g/mol while C is 12 g/mol. Let's solve for amount of C in hydrocarbon.
Mass of C = (14.1 g CO₂)(1mol/44g)(1 mol C/1 mol CO₂)(12 g/mol) = 3.845 g C
So, that means that the mass of hydrogen is:
Mass of H = 4.4 - 3.845 = 0.555 g
Moles C = 3.845/12 = 0.32042
Moles H = 0.555/1 = 0.555
Divide both by the smaller value, 0.32042.
C: 0.32042/0.32042 = 1
H: 0.555/0.32042 = 1.732
We have to get an answer that is closest to a whole number. Let's try multiplying both with 4.
C: 1*4 = 4
H: 1.732*4 = 6.93≈7
<em>Thus, the empirical formula is C₄H₇.</em>
Answer: 1CH+1O₂= 1 CO₂+1H₂O
are
Explanation: coefficients are the 1s. Atoms are C,H,O. Molecules are CH,O₂,CO₂,H₂0. Reactants are CH and O₂. Products are CO₂ and H₂O
