Which of the following is NOT an example of an endothermic reaction?
An ice cube melts on a summer day.
An egg cooks in a frying pan.
Water evaporates off a sidewalk.
Fireworks are displayed in the night sky.

Explanation:

I

have not yet learnt chemistry so sorry

Answer:

350

Explanation:

Answer:

Path length is the overall distance traveled following the path of where the object travel. ... Displacement is the distance from the starting point of the object to its final point irregardless where it travels.

Answer:

Acid :

1) they are sour in taste

2) if we put litmus paper in an acid they turn blue litmus to red and ( red litmus paper colour doesn't change )

3) acids use to react with metals

4) it releases hydrogen (H+) when dissolved in water

5) example : Hydrochloric acid , sulphuric acid , nitric acid etc..

base :

1) they are bitter in taste

2) and the red litmus paper trunes to blue and ( red litmus paper colour doesn't change )

3) it doesn't react with metals

4) it releases hydroxide (OH+) when dissolved in water

5 example : sodium hydroxide, potassium hydroxide etc...

Answer: sorry I didnt know the answer it wont let me get off

Explanation:

Answer:

Explanation:

Read up on this:

https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Book%3A_The_Basics_of_GOB_Chemistry_(Ball_et_al.)/13%3A_Unsaturated_and_Aromatic_Hydrocarbons/13.02%3A_Cis-Trans_Isomers_(Geometric_Isomers)

I think the answer is going to structure of 2-methyl-2-pentene.

Answer:

The percent by mass of carbon tetrachloride in the new solution is 72.6

Explanation:

Molecular weight of Carbon Tetrachloride is 154 g/mol

Molecular weight of CH3COOH is 60g/mol

Mass fraction of CCl4 is 0.5

Mass fraction of CCl4 is (0.5/154)/{(0.5/154) + (0.5/60)}

Mass fraction of CCl4 is X = 0.2803 and Y = 1-X

As per Raoul’s law

Y Pt = X * P1

Pt = X * P1 + YP2

Pt = 0.2803 * 1377 + (1-0.2803) * 519

Pt = 759.557 torr

Substituting the given values we get  

Y1 = X1P1/Pt

Y1 = 0.2803 * 1377/759.557

Y1 = 0.508

Mass fraction  

(0.508)(154)/{( (0.508)(154)) + (1-0.508)(60)}

= 0.726 = 72.6 %

Explanation:

Simply multiply the # of moles of O2 by a molar ratio to give the # of moles of MgO:

#moles O2 × (2 mol MgO/1 mol O2) = # moles of MgO

where the quantity inside the parenthesis is the molar ratio between MgO and O2.

Answer:

IUPAC name is butanol

I hope it's helps you

Answer:

Ionic bonding is the complete transfer of valence electron

Explanation:

In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.

Answer:

48%

Explanation:

Based on Gay-Lussac's law, the pressure is directly proportional to the temperature. To solve this question we must assume the temperature increases and all CO2 remains without reaction. The equation is:

P1T2 = P2T1

Where Pis pressure and T absolute temperature of 1, initial state and 2, final state of the gas:

P1 = 10.0atm

T2 = 1420K

P2 = ?

T1 = 730K

P2 = 10.0atm*1420K / 730K

P2 = 19.45 atm

The CO2 reacts as follows:

2CO2 → 2CO+ O2

Where 2 moles of gas react producing 3 moles of gas

Assuming the 100% of CO2 react, the pressure will be:

19.45atm * (3mol / 2mol) = 29.175atm

As the pressure rises just to 24.1atm the moles that react are:

24.1atm * (2mol / 19.45atm) = 2.48 moles of gas are present

The increase in moles is of 0.48 moles, a 100% express an increase of 1mol. The mole percent that descomposes is:

0.48mol / 1mol * 100 = 48%

Answer:

Please find the solution in the attached file.

Explanation:

Explanation:

Since you're 16, you have to calculate how many seconds you've lived.

16 years × 31,536,000= 504,576,000 pennies.

504,576,000÷58 (for the amount of gold) = 8699586.2069 grams

Then go on from there. Hope that helped!

Solution :

Molar mass of [tex]C_6H_6[/tex] is :

M = 6×12 + 6×1 g

M = 78 g

78 gram of [tex]C_6H_6[/tex] contains [tex]6.022 \times 10^{23}[/tex] molecules.

So, 89.5 gram of [tex]C_6H_6[/tex] contains :

[tex]n = 6.022 \times 10^{23} \times \dfrac{89.5}{78}\\\\n = 6.91 \times 10^{23}[/tex]

Now, from the formula we can see that one molecule of [tex]C_6H_6[/tex] contains 2 hydrogen atom . So, number of hydrogen atom are :

[tex]h = 2\times 6.91 \times 10^{23}\\\\h = 1.38 \times 10^{22}\ atoms[/tex]

Hence, this is the required solution.

Answer:

true

because with the both states we increase the surface of reaction

Answer:

[tex]C_8H_{10}O_2N_4[/tex]

Explanation:

Hello there!

In this case, according to the given information about the empirical formula of this compound, we can infer that these mole ratios can be rounded to the following whole numbers in order to find the empirical formula:

[tex]C_4H_5ON_2[/tex]

Whose molar mass is 97.09 amu and thus, the ratio of the molecular to the empirical molar mass is:

[tex]200/97.09=2.1[/tex]

Which is almost a factor of 2; and therefore, the resulting molecular formula is:

[tex]C_8H_{10}O_2N_4[/tex]

Regards!

Answer:

17.4 L

Explanation:

Step 1: Given data

Step 2: Calculate the volume occupied by 0.775 moles of oxygen at standard temperature and pressure (STP)

At STP, 1 mole of an ideal gas occupies 22.4 L.

0.775 mol × 22.4 L/1 mol = 17.4 L

Answer:

nuclear im not sure but the chances of the answer getting correct is high

Answer:

The concentration of an acid in a solution can be determined by making an acid-base titration. To do this, a known volume of the acid solution is gradually added alkali solution whose concentration is known, until a neutral pH is reached.

Explanation:

Answer:

the packing efficiency is 52.36%

Explanation:

Given the data in the question;

simple cubic unit cell that contains one atom with a metallic radius of 175 pm;

we know that;

Edge length of Simple cubic (a) is related to radius of atom (r) as follows;

a = 2r

since radius r = 175 pm

we substitute

a = 2 × 175 pm

a = 350 pm

Now we get the volume unit;

Volume of unit cell = a³ = ( 350 pm ) = 42875000 pm³

Next we get Volume of sphere;

Volume of Sphere = [tex]\frac{4}{3}[/tex]πr³

Volume occupied by 1 atom = [tex]\frac{4}{3}[/tex] × π × ( 175 pm )³

=  [tex]\frac{4}{3}[/tex] × π × 5359375 pm³

= 22449297.5 pm³

Now, the packing efficiency = ( Volume occupied by 1 atom / Volume of unit cell ) × 100

we substitute;

packing efficiency = ( 22449297.5 pm³ / 42875000 pm³ ) × 100

= 0.523598 × 100

= 52.36%

Therefore, the packing efficiency is 52.36%

Answer: The answer is Iceberg

Answer:

Is it an iceberg?

Explanation:

it floats in water

and you can only see the tip of an iceberg

Hope this helps! :)

Have a great weekend!!

Answer: airbags generally vary between 35 and 60 liters in volume and for the airbag system to activate, it takes about 20 Kgf/cm² of pressure; with this data taken from literature and knowing the temperature of reaction (495 °C), we determine the moles of nitrogen needed from the ideal gas law.

Explanation:

Explanation:

3Ca(s) + 2AlCl3(aq) -> 3CaCl2(aq) + 2Al(s)

According to the question, Ca is the limiting reactant.

Therefore, we equate Ca to Aluminium which is the product whose mass we want to find

Molar mass of Ca- 40g/mol

". ". of Al- 27g/mol

3Ca --> 2Al

3×40 --> 2×27

9.2 --> x

x = 9.2×2×27= 496.8÷120=4.14

Answer:

0.750 g

Explanation:

The reaction that takes place is:

First we calculate how many moles of each reactant were added, using the given volumes and concentrations:

Given that they react in a 1:1 ratio, and that there are less CaS moles than (NH₄)₂CO₃ moles, CaS is the limiting reactant.

We now convert 7.5 mmol CaCO₃ into mg, using its molar mass:

Finally we convert 750 mg to g:

Answer:

FeCl₃ . 6H₂O, BRAINLIST PLZ

Explanation:

1) The chemical formula of iron(III) chloride is FeCl₃ (the oxidation number of Fe is 3+, and the oxidation number of Cl is 1-).

2) The formula that you are lookin for the hydrate is of the type FeCl₃ . n H₂O, where n is the number of water molecules per each unit formula of Fe₂O₃.

3) Find the mass of anhydrous FeCl₃ by difference:

mass of FeCl₃ = mass of the sample - mass of the water in the sample

mass of FeCl₃ = 5.49g - 2.20 g = 3.29 g

4) Convert the mass of FeCl₃ in number of moles

number of moles = mass in grams / molar mass

molar mass of FeCl₃ = 55.845 g/mol + 3×35.453 g/mol = 162.204 g/mol

number of moles = 3.29 g / 162.204 g/mol = 0.0203 mol FeCl₃

5) Convert the mass of water in number of moles:

molar mass of water = 18.015 g/mol

number of moles of water = mass in grams / molar mass = 2.20 g / 18.015 g/mol = 0.122 moles H₂O

6) Find the mole ratio of water to iron chloride:

0.122 mol water / 0.0203 mol iron chloride = 6.01 ≈ 6

Therefore, the complete formula of the hydrate is FeCl₃ . 6H₂O,

Answer:

The valence shells of the atoms are overlapping.

Explanation:

Have a great day

Answer:

A and B

Explanation: