Ask question

Ask question

All categories

2 years ago

13

Write a chemical equation of Dr. Jeff's demonstration using a battery to light steel wool on fire. The battery is used to allow

a current to travel through the steel wool, thus heating it. Steel wood is made from iron (Fe).

1 answer:

dybincka [34]2 years ago

4 0

Answer:

2Fe(s) + 3O2(g) --------> 2FeO3(s)

Explanation:

According to the question, a battery was used to light the steel wool by bringing the terminals very close together. When the battery came into contact with the steel wool, current was sent out through the thin wire. This caused the iron to heat up quite well.

Iron reacts with oxygen under these conditions as follows;

2Fe(s) + 3O2(g) --------> 2FeO3(s)

This is the chemical reaction that occurs when the steel wool is set on fire.

You might be interested in

why is it less effective to wash an insoluble precipitate with 15 ml of water once than it is to wash the precipitate with 3 ml

MArishka [77]

It is less effective to wash an insoluble precipitate with 15 ml of water once than it is to wash the precipitate with 3 ml of water 5 times because commonly, when you clean an <span>indissoluble precipitate with water, the water will not be completely saturated with contaminates. Therefore, the absorption of the contaminates would lower with each wash, since if you only washed it once with a bigger amount or volume of water, it’d become less contaminated with the wash water but it wouldn’t get rinsed numerous times.</span>

6 0

2 years ago

Where in a data table should units of measurement be shown?

Vikentia [17]

The unites of measurement in a data table should be shown in the headings of some columns.

6 0

2 years ago

Read 2 more answers

A tank holds 6.90 m3 of water. What is the volume in ft3? (3.28 ft = 1 m, Remember significant figures, but this answer does not

AleksAgata [21]

Volume of tank = $6.9 m^{3}$ (given)

Since, $1 m = 3.28 ft$

So,

$1 m^{3} = 35.287 ft^{3}$

For $6.9 m^{3}$ :

$6.9\times 35.287 ft^{3} = 243.4803 ft^{3}$

The significant rule for multiplication, states that the number of significant figures in the answer obtained by multiplication is determined by the value with the lowest number of significant digits.

Since, the minimum number of decimal places in the above multiplication operation is 1 so, the final result must be upto 1 decimal place only.

$243.4803 ft^{3} \simeq 243.5 ft^{3}$

Hence, volume in $ft^{3}$ is 243.5.

5 1

2 years ago

Read 2 more answers

What is the sequence of energy transformations that occur in a nuclear reactor? nuclear energy Right arrow. Mechanical energy Ri

Mademuasel [1]

Answer:

NUCLEAR ENERGY -----> MECHANICAL ENERGY -------> THERMAL ENERGY --------> ELECTRICAL ENERGY

Explanation:

In nuclear reactor, various energy transformations occur in order to generate electricity. Nuclear reactor converts the energy released from nuclear fission and the heat generated is removed from the reactor by a cooling system where steam is generated. The steam then drives a turbine which powers a generator to produce electricity.

A nuclear reactor is hence an equipment where nuclear chain reactions occur and control can be obtained. The nuclear reactor uses mostly uranium-235 and Plutonium-239. When these radioactive substances absorbs neutrons, they undergo nuclear fission causing the nucleus to split into two or more smaller compounds with the release of kinetic energy a form of mechanical energy, gamma radiations and others.The kinetic energy is then harnessed in the equipment as heat (thermal energy) which is received by a cooling system and steam is generated. The steam can then power the generator from which electricity is obtained (electrical energy).

So therefore, in a nuclear reactor, the nuclear energy is transformed to mechanical energy and then thermal energy which powers the generation of the electrical energy.

6 0

2 years ago

What would be the composition and ph of an ideal buffer prepared from lactic acid (ch3chohco2h), where the hydrogen atom highlig

Mashutka [201]

Answer:

$P_H =2.86$

$c=1.4\times 10^{-4}$

Explanation:

first write the equilibrium equaion ,

$C_3H_6O_3$ ⇄ $C_3H_5O_3^{-} +H^{+}$

assuming degree of dissociation $\alpha$ =1/10;

and initial concentraion of $C_3H_6O_3$ =c;

At equlibrium ;

concentration of $C_3H_6O_3 = c-c\alpha$

$[C_3H_5O_3^{-} ]= c\alpha$

$[H^{+}] = c\alpha$

$K_a = \frac{c\alpha \times c\alpha}{c-c\alpha}$

$\alpha$ is very small so $1-\alpha$ can be neglected

and equation is;

$K_a = {c\alpha \times \alpha}$

$[H^{+}] = c\alpha$ = $\frac{K_a}{\alpha}$

$P_H =- log[H^{+} ]$

$P_H =-logK_a + log\alpha$

$K_a =1.38\times10^{-4}$

$\alpha = \frac{1}{10}$

$P_H= 3.86-1$

$P_H =2.86$

composiion ;

$c=\frac{1}{\alpha} \times [H^{+}]$

$[H^{+}] =antilog(-P_H)$

$[H^{+} ] =0.0014$

$c=0.0014\times \frac{1}{10}$

$c=1.4\times 10^{-4}$

6 0

2 years ago