All categories

3 years ago

What is a Scientific law

1 answer:

6 0

A scientific law<span> is a statement based on repeated experimental observations that describes some aspects of the universe. A </span>scientific law<span> always applies under the same conditions, and implies that there is a causal relationship involving its elements.</span>

You might be interested in

How many grams of carbon monoxide are needed to react with an excess of iron (III) oxide to produce 198.5 grams of iron? Fe2O3(s

erastova [34]

Answer : The grams of carbon monoxide needed are 148.89 g

Solution : Given,

Mass of iron, Fe = 198.5 g

Molar mass of iron, Fe = 56 g/mole

Molar mass of carbon monoxide, CO = 28 g/mole

First we have to calculate the moles of iron, Fe.

$\text{ Moles of Fe}=\frac{\text{ Mass of Fe}}{\text{ Molar mass of Fe}}=\frac{198.5g}{56g/mole}=3.545moles$

The balanced chemical reaction is,

$Fe_2O_3(s)+3CO(g)\rightarrow 3CO_2(g)+2Fe(s)$

From the balanced reaction, we conclude that

2 moles of iron produces from the 3 moles of carbon monoxide

3.545 moles of iron produces from the $\frac{3}{2}\times 3.545=5.3175$ moles of carbon monoxide

Now we have to calculate the mass of carbon monoxide, CO.

$\text{ Mass of CO}=\text{ Moles of CO}\times \text{ Molar mass of CO}$

$\text{ Mass of CO}=(5.3175moles)\times (28g/mole)=148.89g$

Therefore, the grams of carbon monoxide needed are 148.89 g

7 0

2 years ago

C-12 and C-13 are naturally-occurring isotopes of the element carbon. C-12 occurs 98.88% of the time and C-13 occurs 1.108% of t

Veseljchak [2.6K]

Answer:

c) (12×0.9889) + (13×0.01108)

Explanation:

Given data:

Percentage of C-12 = 98.89%

Percentage of C-13 = 1.108%

Atomic mass = ?

Solution:

98.89/100 = 0.9889

1.108/ 100 = 0.01108

Atomic mass = (12×0.9889) + (13×0.01108)

Atomic mass = (11.8668 + 0.144034)

Atomic mass = 12.01084

6 0

3 years ago

What happened to the size of the sun one carbon and oxygen

Ainat [17]

Answer:

Explanation:

The volume of the Sun is so huge that it could hold over 1 million Earths. The Sun is a typical star, and is also the star that is nearest to the Earth. It is composed of a mixture of 73% hydrogen, 25% helium, and 2% other elements by weight.

4 0

3 years ago

Select the correct answer.

ivann1987 [24]

Answer:

Explanation:

The electronic configuration of N (7 electrons): 1s² 2s² 2p³.

The orbital 1s is filled with two electrons and their spinning direction is opposite and also electrons of 2s.

3p contains (3 electrons) should fill the 3 orbitals firstly. Every orbital contains 1 electron and be in the same spin direction.

So, the right choice is c.

A is wrong because 2 electrons of 3p are paired in the first orbital before filling every orbital.

B is wrong because the 2 electrons of 1s and 2s are in the same direction and also 2 electrons of 3p are paired in the first orbital before filling every orbital.

D is also wrong the 2 electrons of 1s and 2s are in the same direction and the electron in the second orbital of 3p are in opposite direction of the other 2 electrons.

7 0

3 years ago

I've asked before and gotten spammed hopefully I won't get spammed this time please help me with this someone. pls help anyonw

elena55 [62]

Answer:

See below!

Explanation:

A. The picture of the graph is attached. You can tell the amount of protons in an element by looking at the periodic table. The elements are ordered by the number of protons in an element.

B. Carbon and silicon are at the peaks of the chart. The peak is the highest point in a graph.

C. The elements belong to the non-metal group.

D. The halogens are non-metals, and their vapors are colorless.

The halogens are toxic to humans.

Halogen molecules are made of two atoms; they are diatomic.

Halogens react with non-metals to form crystalline compounds that are salts.

The halogens get less reactive going down the group on the periodic table.

Halogens can bleach vegetable dyes and kill bacteria.

E. The picture of the table is attached. To figure which numbers to put where, you need to pay attention to the other numbers. The halogens follow a trend with each of these properties. You have to put in the numbers that fit in among the other numbers.

3 0

3 years ago