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2 years ago

The greeks were the first to use the term _____?

1 answer:

5 0

The greeks were first to use the term atom by the scientist Democritus which he defined as an indivisible and the simplest part of a substance. Neutron was discoverred by the scientist Chadwick, proton was discovered by Sir Ernest Rutherford.For this problem, answer is A.

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Based on the data given, which factor had the greatest effect on the behavior of the gas

Pepsi [2]

Do you have the picture of the data?

6 0

3 years ago

What is the composition, in atom percent, of an alloy that consists of a) 5.5 wt% Pb and b) 94.5 wt% of Sn? Assume that the atom

Anastaziya [24]

Answer : The percent composition of Pb and Sn in atom is, 3.21 % and 96.8 % respectively.

Explanation :

First we have to calculate the number of atoms in 5.5 wt% Pb and 94.5 wt% of Sn.

As, 207.2 g of lead contains $6.022\times 10^{23}$ atoms

So, 5.5 g of lead contains $\frac{5.5}{207.2}\times 6.022\times 10^{23}=1.59\times 10^{22}$ atoms

and,

As, 118.71 g of lead contains $6.022\times 10^{23}$ atoms

So, 94.5 g of lead contains $\frac{94.5}{118.71}\times 6.022\times 10^{23}=4.79\times 10^{23}$ atoms

Now we have to calculate the percent composition of Pb and Sn in atom.

$\% \text{Composition of Pb}=\frac{\text{Atoms of Pb}}{\text{Atoms of Pb}+\text{Atoms of Sn}}\times 100$

$\% \text{Composition of Pb}=\frac{1.59\times 10^{22}}{(1.59\times 10^{22})+(4.79\times 10^{23})}\times 100=3.21\%$

and,

$\% \text{Composition of Sn}=\frac{\text{Atoms of Sn}}{\text{Atoms of Pb}+\text{Atoms of Sn}}\times 100$

$\% \text{Composition of Sn}=\frac{4.79\times 10^{23}}{(1.59\times 10^{22})+(4.79\times 10^{23})}\times 100=96.8\%$

Thus, the percent composition of Pb and Sn in atom is, 3.21 % and 96.8 % respectively.

6 0

2 years ago

According to the article, puberty indicates the beginning of adolescence. How does nutrition influence the start of adolescence?

Arisa [49]

Answer:

<h3> adolescence begins according to your diet</h3>

Explanation <em>unhealthy diet</em> brings about early or late commence of adolescence especially in girls

6 0

1 year ago

What effect will doubling the initial concentration of crystal violet have on the rate

Mnenie [13.5K]

When the initial concentration of crystal Violet is double, the rate of the reaction will rise up about four times the initial rate.

<h3>What is the rate of chemical reaction?</h3>

The rate of a chemical reaction refer to the rate of change in concentration of the reaction over the change in time. Introduction.

When you double the concentration the rate doubles. The rate is proportional to the square of the concentration of a reactant. When the rate is doubled the concentration rate goes up four times. The rate is not affected by the concentration of a reactant.

Learn more about rate of chemical reaction here.

brainly.com/question/24795637

6 0

1 year ago

I need help please asap

Margaret [11]

Answer:

Bonding in chemistry is known as chemical bonding which means the interaction or attraction between molecules.

Chemical bonds are of different type such as ionic, covalent, hydrogen, and metallic. Ionic bonds are formed by the transfer of valence electron from one atom to other and there is unequal distribution of electrons between two or more atoms. Ionic bonds forms two oppositely charges ions positively charged (loses electron) or negatively charged (gains electron).

Covalent bond are the strong chemical bonds that form due to equal sharing of electron pairs between atoms. They form a stable element and have stable attraction or repulsive forces.

8 0

2 years ago