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3 years ago

18. An example of an atom that has no

Chemistry

2 answers:

fgiga [73]3 years ago

7 0

Answer:

C. 2 protons, 2 electrons, and 1 neutron.

Explanation:

An atom with no charge or neutral charge is an atom with a charge of 0.

Neutrons have no charge so they do not affect it.

Electrons have a negative charge and protons have a positive charge. An equal number of protons and electrons will make the charge neutral.

allochka39001 [22]3 years ago

6 0

Answer:

2 protons, 2 electrons, and 1 neutron.

is correct answer

Explanation:

You might be interested in

Scientist can determine the age of ancient objects by a method called radiocarbon dating. The bombardment of the upper atmospher

levacccp [35]

Answer:

28,700 years

1. Data:

a) Half-life: 5730 years

b) Final radioactivity: 68%

2. Solution:

a) <u>Determine the number of half-lives undergone</u>

Since, <em>the radioactivity has decreased to 68%, means that the carbon-14 contanined is has been reduced in </em> 32%: 100% - 68% = 32%.

32 = 2⁵, meaning that five half-lives have passed since the <em>plant material</em> that formed the<em> parchment fragment died</em>.

b) <u>Compute the time of five half-lives</u>:

5 × half-life time = 5 × 5730 years = 28,650 years.

c) <u>Round to the nearest hundred:</u>

28,650 years ≈ 28,700 years

And that is <em>the age of the parchment</em>.

3 0

3 years ago

Name two elements that have properties similar to those of beryllium and have average atomic masses higher than 130

sertanlavr [38]

In the periodic table, elements of the same group are characterized by having the same similar properties.
So, first we will check the elements that lie within the same group as <span>beryllium and then we will attempt to choose the elements with atomic mass higher than 130.

So, elements in the same group as </span>beryllium are: magnesium, calcium, strontium, barium and radium.
Among these elements, we will find that:
radium has atomic mass of 226 amu
barium has atomic mass of 137.327 amu

Based on this, the two elements would be barium and radium.

3 0

3 years ago

Wood burns in the presence of oxygen in the air and produces fire. After all the wood is burned, the fire stops. What is the exc

worty [1.4K]

Answer:

oxygen

Explanation:any reaction with burning involves mixing oxygen

this is correct

hope this helps plzz mark me brainliest

4 0

3 years ago

How many moles is 17.6 g NaOH?

Lynna [10]

Answer:

$\boxed {\boxed {\sf D. 0.440 \ mol \ NaOH}}$

Explanation:

To convert from moles to grams, the molar mass is used (mass of 1 mole). The values are the same as the atomic masses on the Periodic Table, but the units are grams per mole (g/mol) instead of atomic mass units.

<h3>1. Molar Mass</h3>

We are given the compound sodium hydroxide (NaOH) and we need to look up the molar masses of the individual elements.

Na: 22.9897693 g/mol
O: 15.999 g/mol
H: 1.008 g/mol

The formula for the compound has no subscripts, so there is 1 mole of each element in 1 mole of the substance. We can simply add the molar masses.

NaOH: 22.9897693 + 15.999 + 1.008 = 39.9967693 g/mol

This means there are 39.9967693 grams of sodium hydroxide in 1 mole.

<h3>2. Convert Grams to Moles </h3>

Use the molar mass we found as a ratio.

$\frac {39.9967693 \ g \ NaOH}{ 1 \ mol \ NaOH}$

Since we are converting 17.6 grams of NaOH to moles, we multiply by this value.

$17.6 \ g\ NaOH *\frac {39.9967693 \ g \ NaOH}{ 1 \ mol \ NaOH}$

Flip the ratio so the units of grams of NaOH cancel.

$17.6 \ g\ NaOH *\frac {1 \ mol \ NaOH}{ 39.9967693 \ g \ NaOH}$

$17.6 *\frac {1 \ mol \ NaOH}{ 39.9967693}$

$\frac{17.6 }{ 39.9967693} \ mol \ NaOH$

$0.4400355406 \ mol \ NaOH$

<h3>3. Round </h3>

The original measurement of grams has 3 significant figures, so our answer must have the same. For the number we calculated, that is the thousandth place.

0.4400355406

The 0 in the ten thousandths place (in bold above) tells us to leave the 0 in the thousandth place.

$0.440 \ mol \ NaOH$

17.6 grams of sodium hydroxide are equal to <u>0.440 moles of sodium hydroxide.</u>

3 0

3 years ago

5.6 x 10^3 cm = ___cg

NeX [460]

Answer:

560000 cg

Explanation:

5.6 x 10^3 = 5600

1 g = 100 cg

5600 g = 560000 cg

3 0

3 years ago