Which statement is always true about conversation of matter?
The mass of a system does not change during a chemical reaction
If a solid forms the mass of a system increases
If a gas forms the mass of a system decreases
The mass of a system changes when a substance changes from liquid to gas, but it does not change in a chemical reaction

The given question is incomplete, the complete question is:

A chemist adds 35.0mL of a 6.19 * 10^−4/mmol magnesium fluorideMgF2 solution to a reaction flask. Calculate the mass in micrograms of magnesium fluoride the chemist has added to the flask. Round your answer to

3 significant digits.

Answer:

The correct answer is 1.35 microgram.

Explanation:

Based on the given information,

The volume of magnesium fluoride given is 35 ml, and the concentration of magnesium fluoride is 6.19 × 10⁻⁴ mmol/L.

Now the moles of MgF₂ can be determined by using the formula,

Moles = Concentration × Volume

Moles of MgF₂ = Concentration of MgF₂ × Volume of MgF₂

= 6.19 × 10⁻⁴ mmol/L × 35 ml × L/1000 ml

= 217 × 10⁻⁷ mmol

The molecular mass of magnesium fluoride is 62.3 gram per mole

Thus, the mass of MgF₂ is,

= 217 × 10⁻⁷ mmol × 62.3 g/mol

= 13500 × 10⁻⁷ mg

= 1.35 microgram

Answer:

5;11

Explanation:

Answer:

d=m/

Explanation:

d is density, m is mass, v is volume

Given: m =10.4g, v=12.2mL

substituting in equation,

d=10.4/ 12.2

d=0.8524g/mL

To learn more about density:

The density of the liquid is 0.852 g/mL.

To calculate the density of the liquid, we need to use the formula:

Density = Mass / Volume

Given that the mass of the liquid is 10.4 g and the volume is 12.2 mL, we can substitute these values into the formula:

Density = 10.4 g / 12.2 mL

Simplifying this expression, we find:

Density = 0.852 g/mL

Density is a physical property of a substance and is defined as the amount of mass per unit volume. In this case, the density tells us that for every milliliter of the liquid, there is 0.852 grams of mass. The units of grams per milliliter (g/mL) indicate that the density is a ratio of mass to volume.It is important to note that the density of a substance can vary with temperature, so this value is only valid under the conditions at which the measurement was made. Additionally, the density can provide valuable information about the identity of a substance, as different substances have different densities.

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Answer:

Mg-9

N-6

C-2

O-4

Ca-9

P-6

O-24

Explanation:

Answer:

Earlier today, my friend got a call from the company where she had recently applied for a job. They informed her that she had been selected for an interview, which was scheduled for later this week. She was overjoyed and relieved to hear the news, as she had been searching for a job for several months and this was one of the positions she was most excited about. The call was definitely the highlight of her day, and it put her in a great mood for the rest of the afternoon! :) She immediately called her parents and friends to share the good news and celebrate!!

So,

Carbon is the only element that can form so many different compounds because each carbon atom can form four chemical bonds to other atoms and because the carbon atom is just the right, small size to fit in comfortably as parts of very large molecules.

According to the answer options, the only one that makes sense according to the importance of the covalent bonds that carbon can form is D.

Carbon can form so many compounds because its capacity to form single, double, or triple bonds.

Therefore the correct answer is D.

Answer:

Ans: 8.9 NaCl

Explanation:

Ocean water contains 3.5 nacl by mass how much salt can be obtained from 254 g of seawater

Question: Ocean water contains 3.5% NaCl by mass. How much salt can be obtained from 254g of seawater?

Answer:

Nicotinamide adenine dinucleotide

Flavin adenine dinucleotide

Explanation:

hope this helps ^^

The medicine that has to be given by the nurse to prevent cerebral palsy in the new-born is magnesium sulphate.

The term "cerebral palsy" refers to a collection of conditions that impair mobility and posture development and are thought to be caused by non-progressive abnormalities. Insults that caused cerebral palsy are thought to have happened during foetal development or early childhood. A significant risk factor for cerebral palsy is preterm delivery, and that risk rises sharply as gestational age decreases. Right now, 25% of all new occurrences of cerebral palsy are caused by babies delivered before 34 weeks of pregnancy. Cerebral palsy risk is higher when there are several pregnancies. MgSO4 was infused continuously at a rate of 2 g/h for up to 12 hours after a 6 g loading dose. Given before delivery, magnesium sulphate is known to regulate the vasculature and minimize hypoxia effects by neutralising cytokine or excitatory amino acid damage, which may lower the risk.

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If an equation includes 7(CrO₄)₂, the numbers of Cr's and O's atoms that are there are 14 and 56 respectively.

The number of atoms present in a chemical compound can be calculated by multiplying the subscript of the particular element by any coefficient.

According to this question, 7 moles of chromate with the chemical formula; (CrO₄)₂ is given. The number of oxygen and chromium atoms in this compound can be calculated as follows:

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Answer:

The reaction rate decreases with a decrease in temperature. Catalysts can lower the activation energy and increase the reaction rate without being consumed in the reaction. Differences in the inherent structures of reactants can lead to differences in reaction rates.

Explanation:

Answer:

ethical and aesthetic services and direct services

Explanation:

I just took the test and it's NOT indirect services and direct services like the other person said. It's ethical and aesthetic services and direct services.

Answer:

125.4 kilopascals

Explanation:

wkdje

Answer:

125,400 pa = 125.4 kPa

Explanation:

1 pa = 0.001 kPa

&

1 kPa = 1,000 pa

The volume of the gas at 100K If 1 liter of gas at 300 K is cooled to 100K is 0.33L.

The volume of a gas can be calculated using the following formula:

V1/T1 = V2/T2

Where;

According to this question, a gas is in a flexible container. If 1 liter of gas at 300K is cooled to 100K. The volume of the gas is calculated as follows:

1/300 = V2/100

100 × 1 = 300V2

100 = 300V2

V2 = 100/300

V2 = 0.33L

Therefore, the volume of the gas at 100K If 1 liter of gas at 300 K is cooled to 100K is 0.33L.

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The structure given in question is hydrogen bonding. Hydrogen bonding is a special type of dipole-dipole attraction between molecules.

Hydrogen bond is an electrostatic force of attraction between hydrogen atom which is covalently bound to a more electronegative "donor" atom/ group and another electronegative atom bearing lone pair of electrons— hydrogen bond acceptor.

Hydrogen bonding is a special type of dipole-dipole attraction between molecules and not a covalent bond to hydrogen atom. It results from attractive force between hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom and another very electronegative atom.

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Answer: Does the animal prey on other animals? Is the animal a carnivore?

Assuming the number of moles give is of CO₂, since we know that 1 mol is equivalent to 22.4 L in this case, we can use rule of three to answer this:

V ---- n

x ---- 3.75 mol

22.4 L ---- 1 mol

So, we have the follwing relation:

So, we need a volume of 84 L.

Answer:

C. (by comparing the processes of digestion in animals to the process of photosynthesis in plants)

Explanation:

Answer:

The salt and sugar as well as the baby power and granulated sugar are the independent variables.

The dependent variable is how it reacts (will it dissolve or not)

Explanation:

Answer:

luka for MVP

Explanation:

cus he better than lebron and jordan

The amount of heat energy absorbed when 200 grams of water are heated from 20 C to 60 C is 33,440 Joules.

To find the amount of heat energy absorbed when 200 grams of water are heated from 20 C to 60 C, we can use the equation Q = mcAT.
First, we need to find the value of m, which is the mass of the water in grams. In this case, it is given as 200 grams.
Next, we need to find the value of AT, which is the change in temperature in degrees Celsius.

This can be calculated by subtracting the initial temperature from the final temperature, which gives us 60 C - 20 C = 40 C.
The specific heat capacity of water, C, is given as 4.18 Joules per gram per degree Celsius.
Now we can plug in the values into the equation:
Q = mcAT
Q = (200 g) x (4.18 J/g°C) x (40°C)
Q = 33,440 J
Therefore, the amount of heat energy absorbed when 200 grams of water are heated from 20 C to 60 C is 33,440 Joules.

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fluorine is an element on it's own so no

(Answer) Fluorine is considered a molecular element

(Extra) A molecule is a substance that contains two or more atoms of the same element or different elements that are chemically bounded together and can take part in a chemical reaction.

Answer:

so so

Explanation:

this your question?? <_>

Answer:

The common system of naming alcohol in its series is alcohol

600 and 1,300 degrees Celsius

In pretty sure

Filtration is the process of passing a liquid containing contaminants through a filter to get a cleaner liquid.

After filtration impurities are left on the filter when the liquid goes through it, resulting in a cleaner combination. The procedure of separating one ingredient from another in a compound is used in the purification of chemical compounds or any materials. A mixed sample is turned into fresh samples, each of which contains a single ingredient.Separation procedures are then utilised to separate these compounds. These techniques alter the relative proportions of components in a combination.The type of the compounds and the impurities in them influence the purification of organic chemicals and compounds.

Purification of compounds can be done in other methods as well such as distillation, chromatography, sublimation and crystallisation.

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Full question:

What can you conclude after learning about filtration of solutions of organic compounds? Name other methods of purification of compounds.

The distillation temperature would be > 80 degrees. The composition of the few drops of the distillate would be: 40℅ benzene and 60℅

Distillation is a technique used to separate the components of a combination made up of two liquids that mix well. The liquid mixture is boiled, evaporated, condensed, and isolated using this technique.

The boiling point of a liquid is the temperature at which the vapor pressure of the liquid, a pure compound, or a combination equals 1 atm.

We are aware that pure benzene has a boiling point of 80 oC.

Pure toluene has a boiling point of 106 oC.

As benzene has a lower boiling point than toluene, it distills first. Thus, the distillation temperature is greater than 80 oC.

The mixture contains 40 percent benzene and 60 percent toluene by percentage.

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The ratio of the molar heat capacities Cp/Cv for an ideal gas C) The ratio is sometimes greater than 1.

The ratio of the molar heat capacities Cp/Cv for an ideal gas is known as the adiabatic index or heat capacity ratio, denoted by the symbol γ (gamma). The molar heat capacities represent the amount of heat required to raise the temperature of one mole of the gas by one degree Celsius under constant pressure (Cp) or constant volume (Cv) conditions.

For an ideal gas, the molar heat capacity Cp is always greater than Cv because, at constant pressure, the gas is allowed to expand as it is heated, and some of the energy is used to do work against the external pressure. On the other hand, at constant volume, the gas cannot expand, and all of the energy is used to increase the internal energy (temperature) of the gas. Therefore, Cp > Cv and the ratio Cp/Cv (γ) is always greater than 1.

Different gases have different values of γ depending on their molecular structure. Monoatomic gases like helium or argon have a γ value of approximately 5/3 (1.67), while diatomic gases like nitrogen or oxygen have a γ value of approximately 7/5 (1.4). The value of γ can change with temperature, but it is always greater than 1 for an ideal gas.

Therefore the correct option is C

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Answer:

Option C. 88 KJ

Explanation:

The activation energy (Ea) is the minimum energy that reactant must overcome in order for them to proceed to product.

In an energy profile diagram, the activation energy (Ea) is obtained by calculating the difference between the energy of the activation complex (i.e peak) and the energy of the reactant.

With the above information, we shall determine the activation energy (Ea) of the reaction above as follow:

Activation complex = 268.74 KJ

Energy of reactant = 180.74 KJ

Activation energy (Ea) =?

Activation energy = Activation complex – Energy of reactant

Activation energy = 268.74 – 180.74

Activation energy = 88 KJ

Therefore, the activation energy (Ea) of the reaction is 88 KJ

Answer:

88.00 kJ

Explanation:

Answer:

\(T=1235K=962\°C\)

Explanation:

Hello,

In this case, from thermodynamics, it is widely known that the entropy of fusion is defined in terms of the enthalpy of fusion at the fusion temperature (melting point) as shown below:

\(\Delta _fS=\frac{\Delta _fH}{T}\)

Thus, solving for the melting point:

\(T=\frac{\Delta _fH}{\Delta _fS}\)

Hence, for silver:

\(T=\frac{11.30kJ/(mol)*\frac{1000J}{1kJ} }{9.150J/(mol*K)} \\\\T=1235K=962\°C\)

Which is a typical high temperature for a metal such as silver.

Best regards.