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Answer:

"Endothermic reaction: In an endothermic reaction, the products are higher in energy than the reactants. Therefore, the change in enthalpy is positive, and heat is absorbed from the surroundings of the reaction."

Explanation:

When enthalpy is positive and delta H is greater than zero, this means that a system absorbed heat. This is called an endothermic reaction. When enthalpy is negative and delta H is less than zero, this means that a system released heat. This is called an exothermic reaction.

The sign of q for an endothermic process is positive because the system is gaining heat. A chemical reaction or physical change is exothermic if heat is released by the system into the surroundings. Because the surroundings are gaining heat from the system, the temperature of the surroundings increases.

Learn more about the endothermic reaction here: brainly.com/question/6506846

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Answer: cats r alliens because they r kind of like ufos they would usually wonder around rather u know it or not when they spy on us it could b with us sleep cooking anything so they r like aliens

Explanation:

Answer:

7.2

Explanation:

you first have to find the number of moles of nitrogen dioxide by using the number of moles for calcium nitrate and the mole to mole ratios

number of moles of calcium nitrate=mass/mm

=16.4/102

=0.16g/mol

then you use the mole to mole ratios

2 : 4

0.16: x

2x/2=0.64/2

x=0.32g/moles of nitrogen dioxide

then you use the formula for the volume

v=22.4n

=22.4×0.32

=7.2

I hope this helps

1 meter = 1000 km

2500 meter = 2500/1000 km

= 2.5 km

Answer:

1 Ca(NO3)2

Calcium- Ca, Valency 2

Nitrate- NO3, Valency 1

AFTER CRISS CROSS:

Ca1(NO3)2

Ca(NO3)2

2 sodium bicarbonate = NaHCO3

Na = Sodium = (Na)+

HCO3 = bicarbonate = (HCO3) -

Na HCO3

3 magnesium   nitrite

   +2                 _ 1

Mg2(NO3)2

4 Na    Cl

    +1    _1

formula NaCl

5 hydrogen         sulphide  

H                       SO4

+1                       _2

formula H2SO4

6  H    Cl

  +1     _1

HCl

7 AL2     HSO4

  +2        -2

AL2(HSO4)3

8  NH4   Cl

   +1      _1

NH4Cl

9 NH4     SO4

  +1           _2

(NH3)2SO4

10  H   NO3

    +1    _1

HNO3

Explanation:

here's the answer to your question

Answer:

B. Protons and Neutrons

Answer:

Option"B" is correct.

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Answer:

for volume only liters can be used

Explanation:

Answer:

Potentials of any other electrodes are compared with that of the standard hydrogen electrode at the same temperature. Hydrogen electrode is based on the redox half cell: 2 H+(aq) + 2 e− → H2(g)..

The steps involved in the manufacture of sulphuric acid by contact process:

(1) Sulphur (or iron pyrites) are burnt in air to form sulphur dioxide.

  S+O2→SO24FeS2+11O2→2Fe2O3+8SO2

(2) Catalytic oxidation of sulphur dioxide to sulphur trioxide.

  2SO2+O2V2O52SO3ΔrHo=−196.6kJ

The reaction is reversible and exothermic.

(3) Sulphur trioxide is dissolved in 98% sulphuric acid to form oleum (fuming sulphuric acid). 

  SO3+H2SO4→H2S2O7

(4) Oleum is diluted with water to form sulphuric acid of desired concentration.

    H2S2O7+H2O→2H2SO4

            and

Manufacture of H2SO4 by contact process involves three steps:

1. Burning of sulphur in air to generate SO2.

2. Conversion of SO2 to SO3 by oxidation with air in the presence of 

Answer:

which energy?........

Explanation:

..........................

........

....

Answer:

The answer is "Option i"

Explanation:

In this question, only option (i) is correct, and others were wrong which can be defined as follows:

In option (ii):

[tex]Na^+\ (aq)+Cl^- \ (aq) +Ag^+ \ (aq)+NO_3^- \ (aq) \to AgCl\ (s)+Na^+ \ (aq)+NO_3^-\ (aq) \\\\[/tex]

It is the complete ionic equation.

In option (iii):

[tex]CH_3OH\ (g)+O_2\ (g) \to CO_2\ (g)+H_2O\ (g)[/tex]

It is the combustion reaction but a not balanced equation.

In option (iv):

[tex]2H_2O\ (l) \to 2H_2\ (g)+O_2\ (g)[/tex]

It is the  decomposition equation.

In option (v):

[tex]H^+\ (aq) +OH^-\ (aq)\to H_2O\ (l)[/tex]

It is the complete ionic equation.

Answer:

Metals on the left of the Periodic Table.

Non-Metals on the top-right, plus Hydrogen.

Answer:

C 760 mm of hg

because this is the atmospheric pressure at sea level

The empirical formula is the simplest formula of a chemical compound.

To find the empirical formula, we take the following steps;

1) O - 88.10/16,      H - 11.190/1

  O - 5.5,               H - 11.19

  O - 5.5/5.5,        H - 11.19/5.5

  O -  1,                 H - 2

Empirical formula = OH2

2) C - 41.368/12  H - 8.101/1,   N - 32.162/14,   O - 18.369/16

   C - 3,               H - 8,           N - 2,                  O - 1

   C - 3/1,            H - 8/1          N - 2/1                 O - 1/1

    C - 3,             H - 8,           N - 2,                   O - 1

Empirical formula = C3H8N2O

To obtain the molecular formula where n = number of atoms of each element;

Molecular weight = 174.204 g/mol

[ 3(12) + 8(1) + 2(14) + 16]n = 174

n= 174/88

n = 2 (to the nearest whole number)

Hence, we have;

[C3H8N2O]2

The molecular formula is C6H16N4O2

3)  C - 19.999/12,  H - 6.713/1,   N - 46.646/14,   O - 26.641/16

    C - 2,                H - 7,            N -  3,                 O - 2

    C - 2/2,            H - 7/2,         N -   3/2,             O - 2/2

    C - 1,                H - 4,            N -  2,                  O - 1

Empirical formula - CH4N2O

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Answer: A reaction element are those elements that can take part in a chemical reaction.

Explanation:

An element is made up of atoms that has the same atomic number. It is the basic material of which all matter is composed of. These elements cannot be broken down further into smaller substances by any chemical reaction. Each element has a unique number of protons in its atom. For example,

--> a hydrogen atom has 1 proton,

--> a Helium atom has 2 protons,

--> a Lithium atom has 3 protons, and

--> a carbon atom has 6 protons.

A chemical reaction on the other hand involves rearrangement of the constituent atoms of reactants to create different substances as products. The bonds between atoms are either broken or created to form new molecules. There are different types of chemical reaction which includes:

--> Decomposition reaction

--> Neutralization reaction

--> single displacement reaction and

--> combustion reaction.

Answer:

16 g

Explanation:

Step 1: Write the balanced equation

2 Na + Cl₂ ⇒ 2 NaCl

Step 2: Identify the limiting reactant

The theoretical mass ratio (TMR) of Na to Cl₂ is 46:71 = 0.65:1.

The experimental mass ratio (EMR) of Na to Cl₂ is 10:10 = 1:1.

Since EMR > TMR, Cl₂ is the limiting reactant

Step 3: Calculate the mass of NaCl produced

The theoretical mass ratio of Cl₂ to NaCl is 71:117.

10 g Cl₂ × 117 g NaCl/71 g Cl₂ = 16 g NaCl

Answer:

Reducing sugars are sugars where the anomeric carbon has an OH group attached that can reduce other compounds. Non-reducing sugars do not have an OH group attached to the anomeric carbon so they cannot reduce other compounds. ... Maltose and lactose are reducing sugars, while sucrose is a non-reducing sugar

Answer:

In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.

Answer:

They are good electrolytes

Answer:

Is water the only liquid? If not, name 5 more

Water, ethanol, household bleach, blood, paint, milk, gasoline, mineral oil, acetone and butyl alcohol are examples of liquids. Liquids' properties allow them to flow or be poured easily into containers, lava

water is not the only liquid.

Answer:

apple juice, milk, smoothie, blood, urine

Answer:

Reproducible by other scientists

The personal opinion of the scientist

Using vanable conditions for each test

Explanation:

Answer:

the uses of exothermic reactions are:

1) lighting of stove

2) self heating cans

3) hand warmers

4) in some case exothermic process can be used to cook food such as rice  (by adding calcium oxide to water heat is evolved and it helps to cook food )

Explanation:

hope this helps you pls mark me as brainilst

Answer:

The answer is in the explanation.

Explanation:

The KHP is an acid used as standard in titrations to find concentration of bases as NaOH.

The reaction that explain this use is:

KHP + NaOH → KNaP + H2O

where 1 mole of KHP reacts per mole of NaOH

That means, at equivalence point of a titration in which titrant is NaOH, the moles of KHP = Moles of NaOH added

With the moles of KHP = Moles of NaOH and the volume used by titrant we can find the molar concentration of NaOH.

The moles of KHP are obtained from the volume and the concentration as follows:

Volume(L)*Concentration (Molarity,M) = moles of KHP

If the concentration is more or less than 0.100M, the moles will be higher or lower. For that reason, we need to know the concentration of KHP but is not necessary to be 0.100M.