What are chemicals that speed up the rate of chemical change?

Answer:

D

Explanation:

A catalyst is a substance that increases the rate of a chemical reaction by lowering the activation energy without itself being consumed by the reaction.

Activation energy is the minimum amount of energy required for a chemical reaction to proceed in the forward direction.

A catalyst increases the reaction rate by providing an alternative pathway or mechanism for the reaction

Here are some steps i know from my teacher:

When you write a formula from a home you must follow these rules

1) Write down the name you must follow these rules

2)Write down the symbols for the elements and group in the compound of elements

3)Write down the valency

4)Adjust the number of atoms of each element or group valency is the combining capacity of elements with one another.

Explanation:

M = molar mass

p= percentage abundance

[tex]rel.atm.mass = \frac{ M1p1 + M2p2 + M3p3}{100} \\ r.a.m = \frac{24 \times 78.99 + 25 \times 10 + 26 \times 11.01}{100} \\ r.a.m = \frac{1895.76 + 250 + 286.26}{100} \\ = \frac{2432.02}{100} \\ 24.32[/tex]

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Answer:

Strong affinity of HCl gas for moisture in air results in forming of droplets of liquid solution which appears like a cloudy smoke.

Explanation:

#followformore

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i dont know im only doing for points

Answer: They begin to overlap

Answer:

The original marshmallow was named for the inclusion of marshmallow root in the recipe. The roots and leaves of the marshmallow plant contain mucilage, a slimy-textured demulcent best known for its use as a homeopathic cough suppressant. Marshmallow root is considered to be soothing and mildly antimicrobial. It has long been used as an herbal treatment for minor digestive issues and skin irritations, although its use in the creation of its namesake confection has long since fallen by the wayside.

Explanation:

So basically salt makes it strecthy! Please mark brainliest!!

Answer:

The chemical change in the stomach, known as food digestion,  is from the enzymes in the liver and stomach where they break down food molecules into even smaller molecules in order for them to be digested more easily.

Answer:

D

Explanation:

BEcause you are testing which objects will stick. Your control variable will be the sweater. And the number of times you rub the object on the sweter will not make it stick. It will make it stick for a longer period.

Answer:

D. The type of objects you are testing in the experiment

Answer:

25%

Explanation:

Percent by mass is looking at the percentage of mass within a a solution. So since there's 100g of water and 25 grams of sugar, you divide 25 by 100 to get the ratio. Then multiply by 100 to get the percentage.

Answer:

To calculate the number of neutrons, subtract the atomic number (which equals the number of protons) from the mass number.

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Answer: do you guys know the answer

Explanation:

Answer:

gains,oxidizing

Explanation:

Zn(s) + Cu^2+---> Zn^2+(aq) + Cu(s)

I got the answer right on usatp.

There are quite a few ways to add moisture into the air without a humidifier

A few things that can help add moisture are hanging your clothing to dry. hang drying your damp clothes will add moisture to the air over time as it evaporates and it will make your house smell like fresh clothes.

Another thing is a bath,  allow the water to cool off and leave the bathroom door open, the steam will add moisture to the air as the water cools.

This might seem silly but putting bowls or vases of water out on the windowsill on a sunny day mill moistens the air as it evaporates.

You can also get houseplants, moisture evaporates from the leaves and stems of plants. transpiration can help increase the humidity in your home.

not sure if this is the answer you were looking for but if so im glad i could help. have a great day!

Answer:

nucleus

Explanation:

The nucleus contains the majority of an atom's mass because protons and neutrons are much heavier than electrons, whereas electrons occupy almost all of an atom's volume

Answer:

C

Explanation:

running the balloon against your hair

By applying Charles law, the final volume of the gas is equal to 42 mL.

Given the following data:

To find the final volume of the gas, we would apply Charles law:

Charles law states that when the pressure of an ideal gas is kept constant, the volume of the gas is indirectly proportional to the absolute temperature of the gas.

Mathematically, Charles law is given by the formula;

[tex]\frac{V}{T} =k\\\\\frac{V_1}{T_1} = \frac{V_2}{T_2}[/tex]

Where;

Substituting the given parameters into the formula, we have;

[tex]\frac{140}{400} = \frac{V_2}{120} \\\\140 \times 120 = 400V_2\\\\16800 = 400V_2\\\\V_2 = \frac{16800}{400}[/tex]

Final volume = 42 mL.

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Answer:

Decane doesn't have any free electrons because all the electrons of carbon is used for bonding.

Answer: four different types!!!!

Explanation:

A solution of the ionic salt Lihco3 would have 11.3 pH.

In chemistry, salt exists as a chemical compound consisting of an ionic group of positively charged cations and negatively charged anions, which results in a combination with no net electric charge. A common example stands table salt, with positively charged sodium ions and negatively charged chloride ions.

The fragment ions in a salt compound can be either inorganic, such as chloride (Cl−), or organic, such as acetate (CH3CO−2). Each ion can be either monatomic, such as fluoride (F−), or polyatomic, such as sulfate (SO2−4).

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Noble gases are the least reactive of all elements. That's because they have eight valence electrons, which fill their outer energy level. This is the most stable arrangement of electrons, so noble gases rarely react with other elements and form compounds.

Group 18; The Noble Gases contains the elements on the periodic table that would be the least reactive out of all the elements. So, this include any gas element, such as helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and oganesson (Og). Hence, if you have the options:

(The Option in Bold is Correct)

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Considering the definition of STP conditions, 28 grams of O₂ will ocupy at STP 19.6 L.

The STP conditions refer to the standard temperature and pressure. Pressure values at 1 atmosphere and temperature at 0 ° C are used and are reference values for gases. And in these conditions 1 mole of any gas occupies an approximate volume of 22.4 liters.

On the other side, the molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

In this case, you  have 28 g of O₂. The molar mass es 32 [tex]\frac{g}{mole}[/tex]

Next, you can apply the following rule of three: if 32 grams of the compound are contained in 1 mole, 28 grams are contained in how many moles?

[tex]number of moles=\frac{28 gramsx1 mole}{32 grams}[/tex]

number of moles= 0.875 moles

Now, you can apply the following rule of three: if by definition of STP conditions 1 mole of O₂ occupies a volume of 22.4 liters, 0.875 moles occupies how much volume?

[tex]volume=\frac{0.875 molesx22.4 L}{1 mole}[/tex]

volume= 19.6 L

Finally, 28 grams of O₂ will ocupy at STP 19.6 L.

Learn more:

The phrase which best describes the vapor point of a substance is Choice C; the temperature at which additional heat energy causes the substance to change from a liquid to a gas.

The vapour point of a substance by definition is the state of a substance at which upon addition of any amount of heat energy; he substance undergoes a phase change from liquid to solid.

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Explanation:

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Answer:

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Explanation:

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