Which element is most reactive sodium,magnesium, or aluminum and why?

A 1.24g sample of a hydrocarbon, when completely burned in an excess of O2 yields 4.04g Co2 and 1.24g H20. Draw plausible struct

arsen [322]

Answer:

Plausible structure has been given below

Explanation:

Molar mass of $CO_{2}$ is 44 g/mol and molar mass of $H_{2}O$ is 18 g/mol
Number of mole = (mass/molar mass)

4.04 g of $CO_{2}$ = $\frac{4.04}{44}moles$ $CO_{2}$ = 0.0918 moles of $CO_{2}$

1 mol of $CO_{2}$ contains 1 mol of C atom

So, 0.0918 moles of $CO_{2}$ contains 0.0918 moles of C atom

1.24 g of $H_{2}O$ = $\frac{1.24}{18}moles$ $H_{2}O$ = 0.0689 moles of $H_{2}O$

1 mol of $H_{2}O$ contain 2 moles of H atom

So, 0.0689 moles of $H_{2}O$ contain $(2\times 0.0689)moles$ of $H_{2}O$ or 0.138 moles of $H_{2}O$

Moles of C : moles of H = 0.0918 : 0.138 = 2 : 3

Empirical formula of hydrocarbon is $C_{2}H_{3}$

So, molecular formula of one of it's analog is $C_{4}H_{6}$

Plausible structure of $C_{4}H_{6}$ has been given below.

4 0

2 years ago

Drag the tiles to the correct boxes. Not all tiles will be used.

gizmo_the_mogwai [7]

Answer:

metre measures length

kilogram measures mass

time is seconds

Explanation:

I have matched correctly. Just check SI units and there measures.

4 0

2 years ago

7. Write the equation for the positron emission of barium-127.

ziro4ka [17]

The reaction is given by

$\\ \rm\Rrightarrow {}^{127}_{56}Ba\longrightarrow {}^{0}_{+1}\beta+{}^{127}_{55}Cs$

Barium goes underneath beta decay to form Ceaseum

Cs is very mellable element
It can melt on your hand

8 0

1 year ago

1. A 2-kg bowling ball sits on top of a building that is 40 meters tall. (5 pts) Circle one: KE / GPE / both ( can you show work

masha68 [24]

Potential energy is energy due to an object's height above the ground.
Potential energy = mass x gravity x height
Kinetic energy is energy due to the motion of the object.
Kinetic energy = 1/2 x mass x velocity²

1.
The ball is not moving and is at a height above the ground so it has only potential energy.
P.E = 2 x 9.81 x 40
P.E = 784.8 J

2.
The ball is moving and has a height above the Earth's surface so it has both kinetic and potential energy.
P.E = same as part 1 = 784.8 J
K.E = 1/2 x 2 x 5²
K.E = 25 J

3.
The ball has no height above the Earth's surface and is moving so it has only kinetic energy.
K.E = 1/2 x 2 x 10²
K.E = 100 J

4.
50000 = 1/2 x 1000 x v²
v = 10 m/s

5.
39200 = 200 x 9.81 x h
h = 20.0 m

6.
12.5 = 1/2 x 1 x v²
v = 5 m/s
98 = 1 x 9.81 x h
h = 10.0 m

3 0

2 years ago

how do you know the state of a compound when writing out the equation. WILL MARK BRAINLIEST PLEASE HELP!!

tester [92]

Answer:

The state of matter of each compound or molecule is indicated in subscript next to the compound by an abbreviation in parentheses. For example, a compound in the gas state would be indicated by (g), solid (s), liquid (l), and aqueous (aq).

Explanation:

3 0

2 years ago