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3 years ago

What is cement and who invented it?

Chemistry

1 answer:

Sonja [21]3 years ago

5 0

Answer:

Cement is a combination of calcium, silicone, aluminum, iron and lots of other ingredients to make side walks, home made crafts, etc. The person who invented concrete is Joseph Aspdin.

Explanation:

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What is the chemical formula of the salt produced by the neutralization of potassium hydroxide with sulfuric acid?KSO3KSO4K(SO4)

kakasveta [241]

Answer: The salt produced will be $K_{2}SO_{4}$

Explanation:

During a neutralization reaction, an acid reacts with a base for producing the correspondent salt, and water.

The strong acids release all the protons avalaible when are dissolved, such as sulfuric acid. As you can see, sulfuric acid have 2 protons ready for being released ( $H_{2}SO_{4}$ ); and those places have to be occcupied for other ions equivalents to the H+: K+ from KOH in this case.

Therefore the answer will be $K_{2}SO_{4}$ .

6 0

3 years ago

In examining several amino acids, you want to identify the feature or features that differentiate one amino acid from another. W

sergiy2304 [10]

Your answer is C
amino acids are created by a bond of two carbon atoms and each carbon is part of a different group, one negative and one positive. when the chemical reactions occurs, it creates the several diff amino acids

4 0

3 years ago

Read 2 more answers

What is the relative atomic mass of a hypothetical element that consists isotopes in the indicated natural abundances

belka [17]

The given question is incomplete. The complete question is:What is the relative atomic mass of a hypothetical element that consists isotopes in the indicated natural abundances.

Isotope mass amu Relative abundance

1 77.9 14.4

2 81.9 14.3

3 85.9 71.3

Express your answer to three significant figures and include the appropriate units.

Answer: 84.2 amu

Explanation:

Mass of isotope 1 = 77.9

% abundance of isotope 1 = 14.4% = $\frac{14.4}{100}=0.144$

Mass of isotope 2 = 81.9

% abundance of isotope 2 = 14.3% = $\frac{14.3}{100}=0.143$

Mass of isotope 3 = 85.9

% abundance of isotope 2 = 71.3% = $\frac{71.3}{100}=0.713$

Formula used for average atomic mass of an element :

$\text{ Average atomic mass of an element}=\sum(\text{atomic mass of an isotopes}\times {{\text { fractional abundance}})$

$A=\sum[(77.9\times 0.144)+(81.9\times 0.143)+(85.9\times 0.713)]$

$A=84.2amu$

Therefore, the average atomic mass of a hypothetical element that consists isotopes in the indicated natural abundances is 84.2 amu

4 0

3 years ago

Find the volume of a gas if 3.6 mols of the gas is at STP

Digiron [165]

Answer:

81 L gas

General Formulas and Concepts:

<u>Ideal Gas Law</u>

STP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm, 273 K

<u>Stoichiometry</u>

Using Dimensional Analysis

Explanation:

<u>Step 1: Define</u>

[Given] 3.6 mols gas at STP

[Solve] volume (L) of gas

<u>Step 2: Convert</u>

[DA] Set up: $\displaystyle 3.6 \ mol \ gas(\frac{22.4 \ L \ gas}{1 \ mol \ gas \ at \ STP})$
[DA] Multiply [Cancel out units]: $\displaystyle 80.64 \ L \ gas$

<u>Step 3: Check</u>

<em>Follow sig fig rules and round. We are given 2 sig figs.</em>

80.64 L gas ≈ 81 L gas

6 0

3 years ago

If 2.8X10⁻¹⁰% of the atoms of a radioactive isotope disintegrate in 1.0 yr, what is the decay constant of the process?

Marizza181 [45]

Decay constant, proportionality between the size of a population of radioactive atoms and the rate at which the population decreases because of radioactive decay.

<h3>What is decay constant value?</h3>

The rate of disintegration is proportional to the number of atoms at any point in time and the constant of proportionality is called the radioactivity decay constant. The radioactive decay constant for Radium B is approximately 4.3 × 10−4 s−1.

<h3>What is decay constant unit?</h3>

Definition. The decay constant (symbol: λ and units: s−1 or a−1) of a radioactive nuclide is its probability of decay per unit time. The number of parent nuclides P therefore decreases with time t as dP/P dt = −λ. The energies involved in the binding of protons and neutrons by the nuclear forces are ca.

Learn more about decay constant here:

<h3>brainly.com/question/16623902</h3><h3 /><h3>#SPJ4</h3>

7 0

1 year ago