if 500 mL of hydrogen are collected over water at 20 degrees celsius and 18.6psi, what will the volume of the dry gas be at STP

Neon has 2 isotopes. Neon-20 has a mass of 19:992 amu and

Alenkinab [10]

Answer:

20.0928.

Explanation:

The average atomic mass is (90 * 19.992 + 10* 21) / 100

= 20.0928.

6 0

3 years ago

Propane (c3h8) is burned in oxygen to produce carbon dioxide and water. the heat of combustion of propane is -2012 kj/mole. how

Olegator [25]

$C_{3} H_{8} + 5 O_{2} ---\ \textgreater \ 3CO_{2} +4H_{2}O (-2012 \frac{kJ}{mol} )


3 mol 10 mol


C_{3}H_{8} is /excess /reactant

because 3 mol propane require 15 mol oxygen (by reaction)

5 mol oxygen ---1 mol propane, so

10 mol oxygen ---2 mol propane

Only 2 mole propane will be burned,

so 

2012 ( kJ/mol)*2 mol =4024 KJ heat will be given off

Correct answer is number 4.


$

5 0

2 years ago

Which of the following equations has correct formulas and also is a balanced equation?

aliya0001 [1]

Answer : The correct option is, (B)

Explanation :

Balance equation : Balanced equation are those equation in which the number of atoms of each element and the total charge must be same on products side and reactants side.

In the given options, only option (B) equation has correct formula and also a balanced equation.

$2Be+O_2\rightarrow 2BeO$

while the other options has incorrect formulas and also an unbalanced equations.

The correct equation for option A is, $CaCO_3\rightarrow CaO+CO_2$

The correct equation for option C is, $2Mg+O_2\rightarrow 2MgO$

The correct equation for option D is, $KCl+HNO_3\rightarrow HCl+KNO_3$

Hence, the correct answer is, (B) $2Be+O_2\rightarrow 2BeO$

5 0

3 years ago

Two samples of a compound containing elements a and b are decomposed. the first sample produces 15 g of a and 35 g of

Alborosie

According to law of definite proportion, for a compound, elements always combine in fixed ratio by mass.

The formula of compound remains the same, let it be a_{x}b_{y} where, a and b are two different elements.

Since, the ratio of mass remains the same , calculate the ratio of masses of element a and b in both cases

\frac{a}{b}=\frac{15}{35}=\frac{10}{y}

rearranging,

y=\frac{10\times 35}{15}=23.3

Thus, mass of b produced will be 23.3 g.

3 0

3 years ago

PLEASE HELP! WILL MARK BRAINIEST IF ANSWERED CORRECTLY.

ioda

Answer:

H2O is a polar molecule

the H is slightly positive and the O is slightly negative so the Na is attracted to the O side of the water molecule and the Cl is attracted to the H side of the water molecule

Explanation:

3 0

3 years ago