pliz answer 1 & 2 .... I'll tag best answer brainliest .... no spamming ​

Answer:

Option D, Index fossil helps scientists to determine the relative ages of rocks by their positions

Explanation:

Index fossils are arranged in layer in such a way that the lowest layer represent the oldest fossil and the top most layer represents the youngest fossil. Scientist use this concept to determine the relative age of the rocks based on their position beneath the earth’s surface

Hence, option D is correct

Answer:

-96.6°C

Explanation:

Given:

        mass CCl4 = 530.0 g * (1 kg / 1000)

        mass CCl4 = 0.5300 kg

First calculate the molality (m) of the solute, which is the moles of solute divided by the kg of solvent ([tex]\frac{moles}{kg}[/tex]):

molality CHCl3 = (mass moles CHCl3) / (mass CCl4 in kg)

molality CHCl3 = (1.31 mol) / (0.5300 kg)

molality CHCl3 = 2.471698m

Decrease in freezing point of solvent = (Kf) * (molality of solute)

Decrease in freezing point of CCl4 = (Kf) * (molality CHCl3)

Decrease in freezing point of CCl4 = (29.8°C/m) * (2.47m)

Decrease in freezing point of CCl4 = 73.6566°C

Then use the molality of the solute to calculate the change in freezing point and subtract the change from the original freezing point.

Freezing point of solution =

(freezing point of pure solvent) - (Decrease in freezing point)

Freezing point of solution = (-22.9°C) - (73.66°C)

Freezing point of solution = -96.6°C

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Answer:

25.45 Liters

Explanation:

Using Ideal Gas Law PV = nRT => V = nRT/P

V = (1mole)(0.08206Latm/molK)(298K)/(1atm) = 25.45 Liters

Answer:

45 mL

Explanation:

Tenemos los siguientes datos:

V = 1 L

C = 4,5% v/v

El porcentaje en volumen (%v/v) expresa el volumen de soluto (alcohol en este caso) que hay cada 100 mL de solución. Si la solución tiene una concentración del 4,5% v/v eso quiere decir que hay 4,5 ml de alcohol cada 100 ml de solución, de acuerdo a lo siguiente:

4,5% v/v alcohol = volumen alcohol/ volumen solución x 100 = 4,5 mL alcohol/100 mL solución= 4,5 mL alcohol/0,1 L alcohol

Por lo tanto, al multiplicar por el volumen total de la solución (1 L), obtenemos la cantidad total de alcohol:

4,5 mL alcohol/0,1 L alcohol x 1 L = 45 mL

Answer:

Carbon has four valence electrons, so it can achieve a full outer energy level by forming four covalent bonds. When it bonds only with hydrogen, it forms compounds called hydrocarbons. Carbon can form single, double, or triple covalent bonds with other carbon atoms.

The carbon-hydrogen bond (C–H bond) is a bond between carbon and hydrogen atoms that can be found in many organic compounds. This bond is a covalent bond meaning that carbon shares its outer valence electrons with up to four hydrogens. This completes both of their outer shells making them stable.

^Hope it helps, Hazel^

Answer:

go for it

Explanation:

Answer:

I would be happy to help

Explanation:

Answer:

C. Nervous

Explanation:

The nervous system is a system of the body of living organisms which includes the brain, spinal cord and nerves.

Answer:

Option B. It is a basic solution.

Explanation:

To know which option is correct, let us calculate the pH of the solution.

First, we shall determine the pOH of the solution. This is illustrated below:

Concentration of Hydroxide ion, [OH¯] = 3.5×10¯⁶

pOH =.?

pOH = –Log [OH¯]

pOH = –Log 3.5×10¯⁶

pOH = 5.5

Finally, we shall determine the pH. This can be obtained as follow:

pOH = 5.5

pH =?

pH + pOH = 14

pH + 5.5 = 14

Collect like terms

pH = 14 – 5.5

pH = 8.5

The pH scale reads as follow:

0 to 6 => Acidic

7 => Neutral

8 to 14 => Basic

Comparing the pH of the solution (i.e 8.5) with the pH scale, we can conclude that the solution is basic because the pH of solution lies between 8 and 14.

Answer: the place that i put the letters is how it should look also 75% of your peas are green

Explanation:

Statement which is true about ethane and water is that water is likely to have a higher boiling point because it has fewer atoms per molecule.

An atom is defined as the smallest unit of matter which forms an element. Every form of matter whether solid,liquid , gas consists of atoms . Each atom has a nucleus which is composed of protons and neutrons and shells in which the electrons revolve.

The protons are positively charged and neutrons are neutral and hence the nucleus is positively charged. The electrons which revolve around the nucleus are negatively charged and hence the atom as a whole is neutral and stable due to presence of oppositely charged particles.

Atoms of the same element are similar as they have number of sub- atomic particles which on combination do not alter the chemical properties of the substances.

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Answer:

The earth is made of chemical

Explanation:

Explanation:

because of the chemical made up with earth

Answer:

a The molecules of the water in the teacup

hope it helps

Answer:

5 loaves of bread, 5g of yeast

Answer:

d. Solid

Explanation:

It is frozen to be a glacier

Hope this helps :)

Answer: The balanced equation is [tex]AlCl_{3} + 3Cs \rightarrow 3CsCl + Al[/tex]

Explanation:

A chemical equation which contains same number of atoms on both reactant and product side is called a balanced chemical equation.

For example, [tex]AlCl_{3} + Cs \rightarrow CsCl + Al[/tex]

Here, number of atoms on reactant side are as follows.

Number of atoms on product side are as follows.

To balance this equation, multiply Cs by 3 on reactant side and multiply CsCl by 3 on product side.

Hence, now the equation will be as follows.

[tex]AlCl_{3} + 3Cs \rightarrow 3CsCl + Al[/tex]

Here, number of atoms on reactant side are as follows.

Number of atoms on product side are as follows.

Thus, we can conclude that this equation is balanced.

Answer:  1. F

2. F

3. T

4. F

5. T

6. T

Explanation:

I am not sure i'm sorry if it isn't right

Answer:

This is considered a hypothesis because it hasn't been confirmed. It is just a guess.

Explanation:

A hypothesis is a limited explanation of a phenomenon; a scientific theory is an in-depth explanation of the observed phenomenon. Law is a statement about an observed phenomenon or a unifying concept, according to Kennesaw State University. However, Newton's law doesn't explain what gravity is, or how it works.

Answer:

c

Explanation:

A. It is a statement of fact about how nature works instead of an explanation.

B. It provides an explanation for many observations and accepted hypotheses.

C. It describes how to test a possible explanation of one specific relationship.

D. It has not changed over time even though new technology has been developed.

Answer:

2.04moles

Explanation:

The balanced chemical equation of this reaction is given as follows:

Zn + 2HCl → ZnCl2 + H2

Based on the above balanced equation, 2 moles of hydrochloric acid (HCl) reacts to produce 1 mole of Zinc chloride (ZnCl2).

The question states that 148.8 grams HCl reacts. We need to convert this value to mole by using the formula;

mole = mass/molar mass

Molar mass = 36.46g/lol

mole = 148.8/36.46

mole = 4.08moles of HCl

Hence, if 2 moles of hydrochloric acid (HCl) reacts to produce 1 mole of Zinc chloride (ZnCl2).

Then, 4.08moles of HCl will react to produce (4.08 × 1/2)

= 2.04moles of ZnCl2.

Answer:

64852.94 N/m²

Explanation:

From the question,

P = F/A.................... Equation 1

Where P = Pressure of the Elephant on the ground, F = Weight of the Elephant, A = Area of the sole of the four legs.

But,

F = mg.............. Equation 2

Where m = mass of the elephant, g = acceleration due to gravity

Substitute equation 2 into equation 1

P = mg/A............ Equation 3

Given: m = 4500 kg, A = (1700×4) cm² ( The elephant has four legs) = 6800 cm² = 0.68 m²

Constant; g = 9.8 m/s²

Substitute these values into equation 3

P = (4500×9.8)/0.68

P = 64852.94 N/m²

Answer:

c

Explanation:

The elements that will form covalent bonds are Silicon (Si) and nitrogen (N), option C.

A covalent bond is formed between two atoms by the mutual sharing of one or more pairs of electrons. The two atomic nuclei attract these electrons at the same time. When the difference in electro-negativities of two atoms is too small for electron transfer to form ions, a covalent bond forms.

Hydrogen (H₂) is a molecule with a single covalent bond as well as Halogens like Fluorine (F), Chlorine (Cl), Silicon (Si) and nitrogen (N).

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Answer:

no sure

Explanation:

Answer: Hopefully this helps! sorry if not. :))

Speed has a greater impact on mass because its increases in velocity have an exponentially greater impact on translational kinetic energy because kinetic energy is proportional to velocity squared. Doubling an object's mass would only double its kinetic energy, however doubling its momentum would quadruple its velocity.

Answer:

no definite shape

Explanation:

Answer:

Liquids have no definite shape (takes the shape of its container) they have a definite volume. Particles are free to move over each other, but are still attracted to each other.

Explanation:

Hope this helps!

Answer:

gold i believe or possibly bromine

Explanation:

q- how does fluorine react with gold

a- this fluoride compound features gold in its highest known oxidation state. this red solid dissolves in hydrogen fluoride, but these solutions decompose, liberating fluorine.

q- how does chlorine react with gold

a- gold does react with halogens. it'll, for example, react very slowly with chlorine gas at room temperature to form gold chloride, AuCl3. if gold chloride is heated gently, it will decompose to release the pure elements again.

q- how does bromine react with gold

a- gold in bromine solutions dissolves according to electrochemical/chemical (EC) mechanisms. ... in the chemical composition of the mechanism, this monovalent gold bromide disproportionate into gold and stable AuBr −4 , which reports into solution. with respect to pH, there are two characteristic dissolution regions.

** sorry that i can't provide a sure answer**

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have a nice day!

Fluorine will be most reactive with gold.

What is fluorine?

Of almost all of the elements, fluorine seems to be the most electronegative as well as reactive. Fluorine would be a diatomic, pale yellow, extremely corrosive, combustible gas with a strong smell. The lightest halogen would that be. It produces oxygen and even the incredibly corrosive hydrofluoric acid when it combines strongly with water.

Reactivity would be a substance's capacity to chemically combine with several other substances. Iron, for instance, reacts vigorously with oxygen.

As you move down the group, the halogens, which are non-metal elements in Group 7, become less reactive. In contrast to the alkali metals within Group 1 of the particular periodic table, this trend is the opposite. One of the most reactive elements in Group 7 was fluorine.

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