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Answer:

a metal is an element that readily forms positive ions (cations) and has metallic bonds

coke is a strong stimulant made from coca leaves

Answer:

thermal energy: the part of total internal energy that can be transferred (a portion of the kinetic energy)

heat is the thermal energy that flows from one substance to another due to a temperature difference.

Thermal energy is measured in temperature change.

Thermal energy transfer stops when thermal equilibrium is achieved (Both substances at the same temperature).

conduction: Transfer of thermal energy through a solid object like heat transferring up a metal spoon from a hot cup of coffee.

convection: the transfer of thermal energy due to the movement of a liquid or gas caused by differences in temperature. Only in a fluid (liquid or gas). Breezes, ocean currents.

radiation: Transfer energy with or without matter. Warming from the Sun, microwave oven.

Answer:

Conduction is the transfer of thermal energy through direct contact. Convection is the transfer of thermal energy through the movement of a liquid or gas. Radiation is the transfer of thermal energy through thermal emission. Hope this helps!

Explanation:

Answer:

10.56 moles of NO will be produced

Explanation:

The balanced reaction of ammonia, NH₃ with oxygen, O₂ is:

4NH₃ + 5O₂ → 4NO + 6H₂O

Where 5 moles of oxygen react with an excess of ammonia to produce 4 moles of nitrogen monoxude.

If 13.2 moles of O₂ react:

13.2 mol O₂ * (4 mol NO / 5 mol O₂) =

Answer:

a) distance is 4+7+1+8=20 blocks

b) displacement is 10 blocks

Explanation:

find displacement: x and y

x axis displacement = 4-1 = 3 blocks

y axis displacement = -7+8= 1 block

displacement = the square root of 3^2 + 1^2

= 9+1 = 10 blocks.

You can find the angle of displacement with respect to the initial position using trig identities, if you wish.

Answer:

There are 9.8 ×1021. formula units in 10,005.8gCaO 

Answer:

option 3, the leaves higher up need less water since there getting more light and the ones lower need to adapt to gaining more water since they won't be seeing much light

Answer:

yEs

Explanation:

Answer:

1.  A.

2. D.

3. E.

4. B

5. C.

Explanation:

1. The water cycle uses radiant energy from the sun to function

2. Crystals form by crystalization, hence the name.

3. Condensation is when water vapor changes to a liquid.

4. The water cycle is the movement of water on earth on and below it's crust.

5. Transperation is how plants release water into the air. Also how humans sweat.

Have a most wonderous day!

Answer:

Option D. 30 g

Explanation:

The balanced equation for the reaction is given below:

2Na + S —> Na₂S

Next, we shall determine the masses of Na and S that reacted from the balanced equation. This is can be obtained as:

Molar mass of Na = 23 g/mol

Mass of Na from the balanced equation = 2 × 23 = 46 g

Molar mass of S = 32 g/mol

Mass of S from the balanced equation = 1 × 32 = 32 g

SUMMARY:

From the balanced equation above,

46 g of Na reacted with 32 g of S.

Finally, we shall determine the mass sulphur, S needed to react with 43 g of sodium, Na. This can be obtained as follow:

From the balanced equation above,

46 g of Na reacted with 32 g of S.

Therefore, 43 g of Na will react with = (43 × 32)/46 = 30 g of S.

Thus, 30 g of S is needed for the reaction.

Answer:

Answer 'A'

Explanation:

There are 3 acid-base theories.

- Arrhenius Theory

- Bronsted-Lowry Theory

- Lewis Theory

In the Arrhenius and the Bronsted-Lowry Theories, for an acid to be an acid two requirements must be met. That is, the substance must be soluble in water and two, undergo ionization generating a hydronium cation (H₃O⁺) and a base anion (A⁻) in process; i.e., H-Anion + H₂O => H₃O⁺ + Anion⁻.

The Lewis Theory defines acids and bases in terms of electron pair donation (the base) and electron pair acceptor (the acid). This theory does not require the presence of an ionizable hydrogen in the substance of interest, only non-bonded electron pairs (base) and a cationic character that accepts electron pairs without violating the octet rule in chemical bonding.

For the purpose of answering your question, the Arrhenius and Bronsted-Lowry theories are sufficient for defining acids and bases undergoing ionization in aqueous media. With this, one should understand also that acids and bases are classified as strong acids and strong bases (compounds that ionize 100% aqueous media) or weak acids and weak bases (compounds that do not ionize 100% in aqueous media).

Strong Acids* include HCl, HBr, HI, HNO₃, HClO₄ & H₂SO₄ (1st ionization step only). Strong Bases include Group IA and Group IIA hydroxides except for Beryllium Hydroxides. The weak acids are compounds with ionizable hydrogens that are NOT members of the strong 6 listed above. The weak bases are ammonia and ammonia derivatives in aqueous media.

It is recommended that students only need to memorize the strong six acids in that any compound not one of these six with an ionizable hydrogen is a weak acid whether you know its name or not. The weak bases, as mentioned, are ammonia and ammonia derivatives in water. These compounds will undergo coordinate bonding to generate an ionizable compound containing an ammonium cation and hydroxyl anion. The reaction is as follows:

               RNH₂ + H₂O => RNH₃⁺OH⁻(aq) => RNH₃⁺(aq) + OH⁻(aq)

Typically, weak acids and weak bases undergo very limited ionization in the range of 1% to 2%. The compounds remaining are in concentrations of 98% - 99% unionized but form soluble homogeneous solutions.

If you have further questions, kick back a note. Doc

___________________-

*Some scholars include sulfurous acid (H₂SO₃) as a strong acid but analysis shows aqueous solutions - under special conditions - to contain unionized  H₂SO₃ and thus violates the 100% ionization requirement.

Answer:

crystallization

Explanation:

When 490g of sugar is dissolved completely in water at a high temperature ( 100°C ) and the solution is been cooled to a lower temperature ( 20°C ), The dissolved sugar in the solution will start to crystallize, This is because the solubility of sugar in water decreases with a decrease in temperature of water.

Answer:

mostly water

Explanation:

just did he test on edg

Answer:

Charle's Law ... V ∝ f(T); Pressure and Mass remain constant

Explanation:

Charle's Law is one of the empirical gas laws relating the effect of temperature on volume of a gas while pressure and mass (moles) of substance remain constant. Basically, Charle's Law states that the change in volume associated with a confined mass or gas is directly proportional to the applied temperature.

For a directly proportional relationship between Volume (V) and Temperature (T) the empirical formula is written V ∝ T. This is then set in equation form by including a 'proportionality constant' giving V = k·T. In applications, problems generally provide 'initial' Temperature (T₁) and Volume (V₁) along with a final Temperature (T₂) or final Volume (V₂) and asked to calculate the unknown variable. The Charle's Law relationship detailing this is derived as follows:

V = k·T => k = V/T

The k-value is constant for both the initial and final conditions such that...

k₁ = k₂ => V₁/T₁ = V₂/T₂

Example: Assume a gas volume of 25 liters at 25°C, what would be the gas volume if cooled to 0°C?

Set-up a data table

V₁ = 25L     & V₂ = ?

T₁ = 25°C   & T₂ = 0°C => these values need to be converted to Kelvin Temps so as to avoid division by '0'. So...

T₁ = (25 + 273)K = 298K     &     T₂ = (0 + 273)K = 273K

Substituting into V₁/T₁ = V₂/T₂ and solving for V₂ provides the new volume.

25L/298K = V₂/273K => V₂ = (25L)(273K)/(298K) = 22.9L ≅ 23L (2 sig. figs.)

Generally, to check work, examine the change in volume relative to the change in temperature. For a direct proportionality a decrease in temperature as in the example would give a decrease in volume consistent with Charle's Law. Note that 273K/298K  times  25L gives a smaller resulting volume value. If one applies '298K/273K' times the 25L,  a larger value would result and is inconsistent with Charle's Law.  

it should be 50/50 percent

so 50%

hopefully this is right !

Answer: The empirical formula is [tex]CaS[/tex]

Explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of Ca= 55.6 g

Mass of S = 44.4 g  

Step 1 : convert given masses into moles.

Moles of Ca =[tex]\frac{\text{ given mass of Ca}}{\text{ molar mass of Ca}}= \frac{55.6g}{40.08g/mole}=1.38moles[/tex]

Moles of S =[tex]\frac{\text{ given mass of S}}{\text{ molar mass of S}}= \frac{44.4g}{32.06g/mole}=1.38moles[/tex]

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For Ca = [tex]\frac{1.38}{1.38}=1[/tex]

For S = [tex]\frac{1.38}{1.38}=1[/tex]  

The ratio of Ca : S =  1:1  

Hence the empirical formula is [tex]CaS[/tex]

Answer:

When one object uses force to move the other.

Explanation:

This is called Thrust.Thrust is used in airplane engines,or an engine can be  a source of Thrust,we use our legs to Thrust us forward when we walk!

Sir Isaac Newton's third law explains that for every action, or force, in nature, there is an equal and opposite reaction.

Hope that helps!

Answer: m = nM= 242.8 g

Explanation: amount of MgCl2 is same as n(Mg)

M(MgCl2) = 95.21 g/mol

95.21 g/mol is the mass in grams of MgCl[tex]_2[/tex] are produced by 2.55 mol Mg in the reaction Mg + 2HCl ⟶ MgCl[tex]_2[/tex] + H[tex]_2[/tex].

A body's mass is an inherent quality. Prior to the discoveries of the concept of atom as well as particle physics, it was widely considered to be tied to the amount of matter inside a physical body. It was discovered that, despite having the same quantity of matter in theory, different atoms and elementary particles have varied masses.

There are various conceptions of mass in contemporary physics that are theoretically different but physically equivalent. The resistance of the body to accelerate (change of velocity) in the presence of a net force can be measured experimentally as mass. The gravitational pull an object has on other bodies is also influenced by its mass.

m = n×M= 242.8 g

M(MgCl[tex]_2[/tex]) = 95.21 g/mol

Therefore, 95.21 g/mol is the mass in grams of MgCl[tex]_2[/tex] are produced by 2.55 mol Mg in the reaction Mg + 2HCl ⟶ MgCl[tex]_2[/tex] + H[tex]_2[/tex].

To know more about mass, here:

https://brainly.com/question/28704035

#SPJ2

Answer:

humans or animals

Explanation:

Answer:

3, 2

Explanation:

Balanced equation:

N2 + 3 H2 = 2 NH3

Answer:

the answer is c I believe

Answer:

6 mols H2 are needed

Explanation:

N2 = 28.01g/mol

H2 = 2.02g/mol

[tex]\frac{2 mol N_{2} }{1}[/tex] * [tex]\frac{3 mol H_{2} }{ 1 mol N_{2} }[/tex] = 6 mol H2

Answer:

The answer is A. I took the test today.

Explanation:

Explanation:

Salt?%$- RICE BUTTRESS Ê TCHAIKOVSKY

Answer:

Humans are modifying the world in many ways, and not all of them for the better. The changes we cause are often severe challenges to animals, plants and microbes in nature, from the introduction of pathogens or exotic invasive species to adding toxic substance or excessive nutrients, or causing climatic change. Often several changes occur at once. Nelson Hairston's lab focuses on freshwater environments, especially lakes and ponds, where some of the species present respond to environmental change with decreases in their numbers, even to the point of extinction, while others may benefit to excess, becoming so dominant that they present problems, as in the case of harmful algal blooms stimulated by nutrient enrichment or climate warming. Hairston's lab studies how individual species, food webs, and whole ecosystems are altered when the environment changes.

One way that some freshwater organisms respond to environmental change is to evolve rapidly. A marked change in the environment favors some characteristics of plants, animals and microbes over others. These character differences are often genetically based so that favored characteristics may increase in the next generation. The shorter the generation time, the faster this evolutionary change can occur. For example, tiny but abundant plankton, eaten by fish and other larger animals, can become adapted to the changed environment within a few years because their generation time is only a few days. Hairston's lab has shown that planktonic "water fleas" (Daphnia), major consumers of suspended algae in lakes, evolved to be tolerant of harmful algae within a decade of the appearance of blooms. This rapid evolution (termed "evolutionary rescue" in conservation biology) raises many intriguing questions, for all environments, not just freshwater: To what extent can we rely on species adapting rather than going extinct when their environment changes? How does the evolution of a species that plays a critical ecological role alter the interactions it has with other species, and the functioning of the entire ecosystem?

Answer:False

Explanation:Law of Conservation

Answer:

formation of a precipitate.

Explanation:

This is because during production of cheese, citric acid is added to raise the acid level and rennet is added as an enzymes. This make the milk to coagulate and form solid and semi solids. Some part become solid part which is the cheese and the water is separated and it is called whey. That is it separated the solid from the liquid part . The precipitate is the solid part.

Answer: The ratio of NaCN to HCN is, 1.26

Answer:

B

Explanation:

Answer:

i put platinum in edge

Explanation:

Edge doesnt give correct answers on unit tests, but i passed with an 88 :)