I have no idea how to do this and need help

Answer:

D

Explanation:

Hypotheses are educated guesses, and the best answer is the one with an if, as it indicates that it's a guess.

Answer:

letter b should be the answer

The answer is C. 5

Hope I helped

Answer:

D

Explanation:

Answer:

standard carbon atom

Explanation:

Answer:

Explanation:

This is an isotope of carbon, more specifically, carbon-14. Carbon 14 has 6 protons, making the element carbon, and eight neutrons since 14-6 = 8.

Answer:

Nobles Gases Are the group of elements which are generally unreactive

Answer:

okay so basically what you are being tested is if you know the difference between simple and fractional distillation and okay you can evaporate the mixture but you won't obtain water so you will use simple distillation to obtain both salt and water

Answer:

36 electrons

Explanation:

But Bromine anion with a charge of -1 has one extra electron so 35 +1 = 36 electrons.

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:

Explanation:

D = mass/volume.

for the units, I'll take it in g/L but I don't know which units you want.

4.44*10^5 mg =  0.444 grams.

0.444/7 = 0.0634 g/L

Answer:

The mass percentage composition of nitrogen in the sample of the cleaning detergent is approximately 16.78%  

Explanation:

The given mass of the sample of the cleaning detergent, m₁ = 20.5 g

The mass of the ammonium hydroxide, NH₄OH in the detergent, m₂ = 8.61 g

The molar mass of NH₄OH = 35.04 g/mol

The molar mass of nitrogen, N = 14.01 g/mol

Therefore, the mass, m₃ of nitrogen, N, in 8.61 g of ammonium hydroxide, NH₄OH, is found as follows;

m₃ = (14.01/35.04) × 8.61 g = (402,087/118,800) g ≈ 3.44 g

The mass of nitrogen, N, in the ammonium hydroxide, NH₄OH, contained in the 20.5 g sample of the cleaning agent, m₃ ≈ 3.44 grams

The percentage composition of nitrogen in the sample of the cleaning detergent, %N is given as follows;

[tex]\% Composition = \dfrac{Mass \ of \ component}{Total \ mass \ of \ cleaning \ detergent} \times 100[/tex]

Therefore;

%N ≈ ((3.44 g)/(20.5 g)) × 100 ≈ 16.78 %

The percentage composition of nitrogen, %N ≈ 16.78%.

Answer: 52.17%

Explanation:

Number of matches in the box = 46

Number of matches that lit on the first strike = 22

Number of matches that did not light on the first strike = 46 - 22 = 24

Therefore, the percentage of the matches in the box did not light on the first strike will be:

= (Number of matches that did not light on the first strike / Number of matches in the box) × 100

= 24/46 × 100

= 52.17%

Therefore, the percentage of the matches in the box that did not light on the first strike is 52.17%.

Answer:

1A Alkali Metals

6A Chalcogens

7A Halogens

Answer:

alkali metals, chalcogens, halogens

Explanation:

Group 1A is alkali metals

Group 6A is chalcogens

Group 7A is halogens

Answer:

D

Explanation:

The correct answer would be that the thermal energy of the sun is transferred to the pavement.

Thermal energy refers to the internal energy possessed by a system by virtue of the movement of molecules within such a system. In other words, it is the heat energy possessed by a system.

When the thermal energy from the sun warms the pavement, it means that the thermal energy from the sun has been successfully transferred to the pavement. Thermal energy can be transferred by conduction, convection, or by radiation depending on whether the system is a solid, liquid, gas respectively.

The correct option is, therefore, D.

Answer:

Letter b so F

Explanation:

I hope this help

Explanation:

All five ions have an equal number of electrons and therefore share the same electron configuration. For example, a neutral calcium atom (Z=20) has 20 electrons; it loses two of them to form a Ca2+ cation, which would thus contain 20−2=18 electrons. Similarly, a phosphorus atom (Z=15) gains three electrons to form a P3− anion that contains 15+3=18 electrons.

Positively-charged protons in the nuclei attract the negatively-charged electron cloud. Each proton carries a +1 charge; the more protons an atom or ion contains the stronger the attraction it poses on its electron cloud. A nucleus of strong positive charge pulls its electron cloud towards itself tightly such that the latter would have a small radius.

The periodic table is arranged in the order of increasing proton number. Phosphorus comes the first among the five species and contains the least number of protons. Its ion would be the largest among the five. Calcium comes the last and forms the smallest ion.

Number of protons per nucleus P<S<Cl<K<CaStrength of Electrostatic attraction on the electron cloud P<S<Cl<K<CaIonic radius P3−>S2−>Cl−>K+>Ca2+

Answer:

No Sodium(Na) in methylene

Explanation:

Methylene is an organic compound

Answer:

They are good electrolytes

Answer:

Gases expand the most upon heating because the intermolecular space is more than in solids or liquids.

Explanation:

hopes it helps

Answer:

the volume of the acid is 250 mL.

Explanation:

Given;

number of moles of the Hcl acid, n = 0.5 mol

concentration of the acid, C = 2.0 M = 2 mol/L

let the volume of the acid = V

The volume of the acid is calculated by applying the following equation;

n = CV

V = n/C

[tex]V= \frac{0.5 \ mol}{2 \ mol/L}[/tex]

V = 0.25 L

V = 250 mL

Therefore, the volume of the acid is 250 mL.

Answer:

Iconic bond

Explanation:

Exothermic reaction is where there is release of energy during a reaction

The enthalpy of exothermic reaction is negative

The relation between energy of products, reactants and enthalpy of reaction is

Enthalpy of reaction =  sum of enthalpy of formation of products - sum of enthalpy of formation of reactants .

As enthalpy of reaction is negative, it means the enthalpy of products is less than the enthalpy of reactants  so answer is :

In an exothermic reaction the energy of the product is less than the energy of the reactants.

C.

An endothermic reaction is a reaction that absorbs heat from the surroundings. That means that the energy of the system must increase. Therefore, the answer must be C as the products should have higher energy than the reactants.

Answer: Fluorite

Explanation: Minerals are naturally occurring inorganic materials with definite chemical compositions and definite physical properties. Hardness and Streak are both physical characteristics used in identifying minerals. The colour of a mineral’s powder defines its streak (it does not change from mineral to mineral) and a streak of white shows that such mineral has a calcium fluoride making it a fluorite.  To check streak, one simply scrapes the mineral across an unglazed porcelain plate.

Hardness on the one hand, is the resistance to cutting, scratching, abrasion or indentation of minerals.  Mineral hardness is specified by the Mohs hardness scale when working with hand samples, and the scale ranges from 1 (very soft like talc) to 10 (as hard as diamond). A hardness of 4 also put such mineral into the fluorite range indicating that it is harder than calcite, but softer than feldspar.

In conclusion, the tests show that the mineral in question is a fluorite.

Answer:

chắc là câu B í

Explanation:

Answer:

The FitnessGram™ Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. [beep] A single lap should be completed each time you hear this sound. [ding] Remember to run in a straight line, and run as long as possible. The second time you fail to complete a lap before the sound, your test is over.

Answer:

The mass of oxygen in 45.0 g sample of calcium carbonate is approximately 21.58 g

Explanation:

The chemical formula for calcium carbonate is CaCO₃

The molar mass of CaCO₃ = 100.0869 g/mol

The mass of oxygen in one mole of CaCO₃ = 3 × 15.999 g = 47.997 g

The mass of oxygen in 45.0 g sample of CaCO₃, m, is goven as follows;

m = 45.0/100.0869 × 47.997 g ≈ 21.58 g

The mass of oxygen in 45.0 g sample of calcium carbonate, m ≈ 21.58 g

I guess ensuring that you don't suck the insects or specimen collected by ensuring there is a net in the pooter

Complete Question

A guest orders a drink that contains 4 1/2 ounces of 80-proof liquor. Approximately how many drinks does this beverage contain?

Answer:

[tex]No\ of\ drinks =3[/tex]

Explanation:

From the question we are told that:

Ordered drink 4 1/2 ounces of 80-proof liquor

Generally

80-proof liquor contains 40\% alcohol

Giving the drink a standard 1.5 ounce of distilled spirit

Therefore

[tex]No\ of\ drinks =\frac{4.5}{1.5}[/tex]

[tex]No\ of\ drinks =3[/tex]

Answer:

AgNo3+Mgcl2--->Agcl2+Mg(No3)2

I hope this helps