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2 years ago

Can someone please help me with this? thank you!

Chemistry

1 answer:

Kamila [148]2 years ago

6 0

Answer:

Sulfur — S

calcium — Ca

carbon — C

silver — Ag

gold — Au

helium — He

hydrogen — H

should become easier for you to memorise them as you go on in life (meaning going up a grade… grade 7 to 8 to 9 to 10 until you reach college and whatnot)

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Sammy and Marisa are asked to determine what kind of bonds are present in the

kotykmax [81]

Answer:

I think Sammy is right because I'm sure the compound contains ionic bonds

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2 years ago

Classify unopened root beer as an element, a compound, a homogeneous mixture, or a heterogeneous mixture

maxonik [38]

The different state of material based on its ingredients are-

1. Compound: The compound is in which there are more than one molecule in which chemical bond is there.

2. Mixture: It is basically presence of two or more compounds in which there is no chemical bonds.

The mixture may be of two types (i) homogeneous and (ii) Heterogeneous. In the homogeneous mixture there is uniformity of the mixed compound (like air in water) and some chemical process is needed to separate the compounds. Whereas heterogeneous mixtures (like chalk in water) are easily separable by any physical process.

In the root beer which is a soft drink which is obtained in different flavor sometime with caffeine and without caffeine. The unopened bottle of root beer is homogeneous mixture.

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3 years ago

Based on the kinetic molecular theory, which of the following statements is correct about a sample of gas at a constant temperat

Scilla [17]

Answer:

C) It has a constant average kinetic energy

Explanation:

The average kinetic energy of the particles in a gas is directly proportional to the temperature of the gas, according to the equation.

k is the Boltzmann's constant

T is the absolute temperature of the gas

Therefore, temperature of a gas is a measure of the average kinetic energy of the particles.

In this problem, we are told that the gas is at constant temperature (and volume): therefore, according to the previous equation, this means that the average kinetic energy is also constant.

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3 years ago

What is the pH of a mixture of 0.042 M NaH2PO4 and 0.058 M Na2HPO4? Hint: The pKa of phosphate is 6.86.

AlekseyPX

Answer:

The pH value of the mixture will be 7.00

Explanation:

Mono and disodium hydrogen phosphate mixture act as a buffer to maintain pH value around 7. Henderson–Hasselbalch equation is used to determine the pH value of a buffer mixture, which is mathematically expressed as,

$pH=pK_{a} + log(\frac{[Base]}{[Acid]})$

According to the given conditions, the equation will become as follow

$pH=pK_{a} + log(\frac{[Na_{2}HPO_{4} ]}{[NaH_{2}PO_{4}]})$

The base and acid are assigned by observing the pKa values of both the compounds; smaller value means more acidic. NaH₂PO₄ has a pKa value of 6.86, while Na₂HPO₄ has a pKa value of 12.32 (not given, but it's a constant). Another more easy way is to the count the acidic hydrogen in the molecular formula; the compound with more acidic hydrogens will be assigned acidic and vice versa.

Placing all the given data we obtain,

$pH=6.86 + log(\frac{0.058}{0.042})$

$pH=7.00$

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3 years ago

A ________ reaction occurs when one compound reacts and is broken down into different elements or simpler compounds?

faust18 [17]

Answer: decomposition

Explanation:

1 . Combustion is a type of chemical reaction in which a hydrocarbon reacts with oxygen to form carbon dioxide ans water along with liberation of large amount of energy.

2. Decomposition is a type of chemical reaction in which a single reactant gives two or more than two products.

$CaCO_3\rightarrow CaO+CO_2$

3. Single replacement is a type of chemical reaction in which a more reactive element displaces the less reactive element from its slat solution.

4. Synthesis is a type of chemical reaction in which two or more than two reactants combine together to give a single product.

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3 years ago

Read 2 more answers