HEEEEeEELP PLEasE! IS SCIENCE

A 0.216 g sample of an aluminium compound X reacts with an excess of water to produce a single hydrocarbon gas. This gas burns c

makkiz [27]

0.216g of aluminium compound X react with an excess of water water to produce gas. this gas burn completely in O2 to form H2O and 108cm^3of CO2 only . the volume of CO2 was measured at room temperature and pressure

0.108 / n = 24 / 1
n = 0.0045 mole ( CO2 >>0.0045 mole
0.216 - 0.0045 = 0.2115
so Al = 0.2115 / 27 => 0.0078 mole
C = 0.0045 * 1000 => 4.5 and Al = 0.0078 * 1000 = 7.8

7 0

2 years ago

Diffusion is a general term referring to the net movement of atoms and molecules along a concentration gradient, from an area of

aniked [119]

Answer:

Higher concentration to an area of lower concentration

Explanation:

When you open a perfume bottle at a corner of a room, after a while, its fragrance can be perceived across a distance at the other end of the room. This is because, molecules of the compound in the fragrance have moved from the area of higher concentration in the perfume bottle, across a concentration gradient to a region of lower concentration at the other end of the room. This is diffusion.

7 0

2 years ago

(a) A gas fills completely the

ohaa [14]

Answer:

a)The force of attraction between particles of gas is negligible. Because of this, particles of gas move in all directions. Thus, a gas fills the vessel completely in which it is kept.

b)Because of negligible force of attraction between particles of gas, the particles of gas have the highest kinetic energy. These properties enable the particles of gas to move in all directions and hit the walls of container from all sides. Because of this a gas exerts pressure on the walls of the container in which it is kept.

c): A wooden table has fixed shape and fixed volume, which are the main characteristics of solid. Thus a wooden table should be called a solid.

8 0

2 years ago

To begin the experiment, 1.11g of methane CH4 is burned in a bomb calorimeter containing 1000 grams of water. The initial temper

yaroslaw [1]

In order to calculate the enthalpy of the reaction, we first calculate the heat released using the given formula.
Q = mc<span>ΔT
Q = 1000 x 4.184 x (35.65 - 24.85)
Q = 45187.2 J = 45.2 kJ

Now, we determine the moles of methane that were burned.
Moles = mass / Mr
Moles = 1.11 / (12 + 4)
Moles = 0.07

The enthalpy of a reaction is the energy released per mole, so the enthalpy in this case is:
</span>ΔH = 45.2 / 0.07
ΔH = 645.7 kJ/mol

8 0

3 years ago

Hydrogen cyanide is used to prepare sodium cyanide, which is used in part to obtain gold from gold-containing rock. If a reac- t

Sliva [168]

Answer:

Mass of HCN produced = 6.75 g

Explanation:

Reaction is as follows:

$2NH_3+3O_2+2CH_4 \rightarrow 2HCN + 6H_2O$

First calculate the no. of moles of each chemical species.

molecular mass of $NH_3$ is 17 g/mol

No. of mol of $NH_3$ = 11.5/17 = 0.676 mol

Molecular mass of $O_2$ = 32 g/mol

No. of mol of $O_2$ = 12/32 = 0.375

Molecular mass of $CH_4$ = 16 g/mol

No. of mol of $CH_4$ = 10.5/16 = 0.656 mol

from the balanced chemical reaction, it is clear that 2-moles ammonia reacts with 3 moles oxygen and 2 moles methane to form 2 moles of HCN.

or, 1-mol ammonia reacts with 1.5 mol oxygen and 1 mol methane to form 1 mol of HCN.

Thus, no. of oxygen present is less than required and so it will act as limiting reagent.

From the chemical equation,

3 moles oxygen produces 2 moles HCN

or one mole oxygen produces (2/3) moles HCN

0.375 moles oxygen produces (2/3) × 0.375 HCN = 0.25 moles of HCN

molar mass of HCN = 27 g/mole

Mass = mol × molar mass

mass of HCN = 27 × 0.25 = 6.75 g

8 0

3 years ago