Answer:
A
Explanation:
We are usually asked to close the valve of the gas cylinder in our various kitchens at home <u>due to the inflammable property of the Liquified Petroleum Gas.</u>
<em>Without closing the valve, the LPG would diffuse into our homes, and any form of spark would cause an explosion and lead to a fire. Lives and properties could be lost in the process.</em>
The correct option is A.
The empirical formula for the compound is - P₂O₅
the empirical formula is the simplest ratio of whole numbers of components in a compound.
molecular formula is the actual ratio of components in a compound.
we have to first find the number of empirical units in the molecular formula
molecular mass - 283.89 g/mol
mass of empirical formula - 283.8 g
number of empirical units - 283.89 g/mol / 283.8 g
number of empirical units - 1.000
therefore empirical formula = molecular formula
molecular formula - P₂O₅
a) To find the mass after t years:we will use this formula:
A = Ao / 2^n when A =the amount remaining
and Ao = the initial amount
and n = t / t(1/2)
by substitution:
∴ A = 200 mg/ 2^(t/30y)b) Mass after 90 y :by using the previous formula and substitute t by 90 y
A = 200mg/ 2^(90y/30y)
∴ A = 25 mgC) Time for 1 mg remaining:when A= Ao/ 2^(t/t(1/2)
so, by substitution:
1 mg = 200 mg / 2^(t/30y)
∴2^(t/30y) = 200 mg by solving for t
∴ t = 229 y
The correct answer would be equation 4, because there are 4 Hydrogens and 2 Oxygens on each side of the equation making it balanced.
Answer:
The answer to your question is 7.4 moles of Aluminum
Explanation:
Data
moles of Al = ?
moles of Al₂O₃ = 3.7
Balanced chemical reaction
4 Al + 3 O₂ ⇒ 2 Al₂O₃
To solve this problem use proportions and cross multiplication. Use the coefficients of the balanced chemical equation.
4 moles of Aluminum ----------------- 2 moles of Al₂O₃
x ----------------- 3.7 moles of Al₂O₃
x = (3.7 x 4) / 2
x = 14.8 / 2
x = 7.4 moles of Aluminum
