Which substance is the least toxic?
a. chlorine (LD50 = 850 mg/kg)
b. vitamin A (LD50 = 2000 mg/kg)
c. cola (LD50 = 140 mg/kg)
d. aspirin (LD50 = 200 mg/kg)

Answer:

That would be codes unregonizable

Explanation:

Answer:

creo que es R no se puede ser

Answer:

I believe your answer is B. Experimental research may lead to understanding descriptive research.

Generally, experimental research is a trial and error method that tests the hypothesis of descriptive research. Descriptive research being the theoretical or studied characters of a topic.

Please let me know if I had this wrong, and I'll do some extra research for you.

Answer:

Part 1: 229.95g

Part 2: 598.5g

Part 3: 12.6g

Explanation:

Note: I learned this last week. Answer not sure.

Pls tell me if i got it right or wrong.

Mg + HCl - > MgCl2 + H2

First, balance the equation.

There is only 1 H and 1 Cl at the left side. BUT there are 2 Cl and 2 H at the right side. So you can add a 2 in front of HCl to balance it.

Mg + 2HCl - > MgCl2 + H2

Formula 1: (n= m/mr)

n = moles, m= mass, mr = molecular mass

Formula 2: (n= v/24)

v = volume

Part 1

What mass of HCl is consumed by the reaction of 3.15 mol of magnesium?

Ratio of

(look at the number in front of each)

2HCl : Mg

2 : 1

(3.15 x 2) : 3.15 moles

6.3 moles : 3.15 moles

So 2HCl has 6. 3 moles

Now use formula 1 (n = m/mr)

Calculate molecular mass of HCl

Check your periodic table

mr of HCl =(1 + 35.5) = 36.5

6.3 = m/36.5

m = 229. 95grams

Part 2

What mass of MgCl2 is produced? Answer in units of g.

Ratio of

2HCl : MgCl2

(1 +35.5) : (24+35.5x2)

36.5: 95

229.95g :?

229.95g : 598.5g

m = 598.5g

Part 3

What mass of H2 is produced? Answer in units of g.

2HCl : H2

36.5 : 2

229.95g :?

229.95g : 12.6g

m = 12.6g

Answer: The balanced molecular equation is:

[tex]Na_2CO_3(aq)+FeCl_2(aq)\rightarrow 2NaCl(aq)+FeCO_3(s)[/tex]

The ionic equation is:

[tex]2Na^+(aq)+CO_3^{2-}(aq)+Fe^{2+}(aq)+2Cl^-\rightarrow 2Na^+(aq)+2Cl^-(aq)+FeCO_3(s)[/tex]

The net ionic equation:

[tex]Fe^{2+}(aq)+CO_3^{2-}(aq)\rightarrow FeCO_3(s)[/tex]

Explanation:

A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.

The balanced molecular equation is:

[tex]Na_2CO_3(aq)+FeCl_2(aq)\rightarrow 2NaCl(aq)+FeCO_3(s)[/tex]

Spectator ions are defined as the ions which does not get involved in a chemical equation or they are ions which are found on both the sides of the chemical reaction present in ionic form.

The ionic equation is:

[tex]2Na^+(aq)+CO_3^{2-}(aq)+Fe^{2+}(aq)+2Cl^-(aq)\rightarrow 2Na^+(aq)+2Cl^-(aq)+FeCO_3(s)[/tex]

The ions which are present on both the sides of the equation are sodium and chloride ions. and hence are not involved in net ionic equation.

The net ionic equation:

[tex]Fe^{2+}(aq)+CO_3^{2-}(aq)\rightarrow FeCO_3(s)[/tex]

Answer:

HNO3 + KOH → _KNO3___ + __H2O___

Explanation:

It's balanced

hope it helps

Answer:

zinc

Explanation:

Answer:

cadmium has a greater mass.

explanation:

zincs mass: 65.38

cadmiums mass: 112.411

Answer:

9300 grams = 9.3 kilograms hope it helps

Answer:

1

Explanation:

Warm and cold air fronts with points labeled 1 through 4, cold air entering from the left and moving down. Therefore, the correct option is option 1.

The term "air" is used to refer generally to the concoction of gases that composes the Earth's atmosphere. Nitrogen makes up the majority of this gas (78%), with oxygen, water vapor, argon, carbon dioxide, and trace gases also present.

There is no color or smell in pure air. Dust, pollen, and spores are common airborne contaminants; additional pollutants are alluded to as "air pollution." Since there isn't air in space, the so-called air on another planet, like Mars, would have different manufacturer. Warm and cold air fronts with points labeled 1 through 4, cold air entering from the left and moving down.

Therefore, the correct option is option 1.

To know more about air, here:

https://brainly.com/question/7671110

#SPJ6

Answer:

In short, the thermal conductivity of a material is how readily that material absorbs and transmits (releases) energy. When the fire or heating element of a range comes in contact to a pan, the energy from the heat source is transmitted to the pan. This increases the internal kinetic energy of the pan (commonly called "heating up"). The heated material then transmits the energy to nearby materials that are at a lower average molecular kinetic energy level (at a lower temperature than the material). The higher the thermal conductivity of the material, the faster it will heat up and also, the faster the heated area will spread to unheated areas of the same piece of material.

For example, if we placed a large sheet of stainless steel (fairly low thermal conductivity as cooking materials go) on a burner and turned on the burner, the area directly under the burner would get hot while the rest of the sheet slowly heats up. The burner imparts heat quickly only to the region of steel directly over it. The rest of the pan heats up from the conduction of the heat from that spot. When the outer edges of the sheet have reached a hot temperature, the spot directly over the burner would be extremely hot. The figure below shows an example of the temperature of the sheet of steel over a gas burner. The hottest parts are shown in white, hot is red and cool is blue.

Explanation:

No explanation hope i'm not wrong

Answer:

the answer is d.

1. Write the symbols for each element.

2. Find the charge for each element using the Periodic Table. Write it above each element. (because there is a (III) after nickel, the charge of nickel is +3. oxygen is in group 16, which means it has a -2 charge.)

3. See if the charges are balanced (if they are you're done!)

- when you criss cross (getting Ni2O3, the charges are canceled out, so the equation is balanced.

if you still need help or if this is confusing, look up How to Write the Formula for Nickel (III) oxide  by Wayne Breslyn on YT.

Answer:

D.) Ni2O3

Explanation:

edge 2021 (just needed the daily answer)

B.It will rotate and be in the sun.

Answer:

no lo sé bb 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100

Answer:

this would be the .04 it is very simple

Explanation:

The car is not accelerating, because the car is driving at a constant speed of 20 miles per hour.

Answer:

For most of its active life, a star shines due to thermonuclear fusion of hydrogen into helium in its core, releasing energy that traverses the star's interior and then radiates into outer space. At the end of a star's lifetime, its core becomes a stellar remnant : a white dwarf , a neutron star , or, if it is sufficiently massive, a black hole .

Explanation:

Answer:

its nuclear fusion

Explanation:

Answer:

Solarpannels? I honestly don't know I'm just trying to be helpful.

Answer:i dont even know myself :p

Explanation:

Answer:

this is my old account and these still dont have answers

Explanation:

Answer:

What substance changed physically under all three condition? Copper Wire

What substance changed chemically under all three condition? Steel Wool

What evidence indicates a chemical reaction is occurring? New gases are produced; A phase change has occurred; A color change

Select the three answers that are examples of a chemical reaction. The mixing of an acid and base shows an increase in temperature; after baking bread there is a new odor or smell; when hair is bleached it changes to a lighter color

Which data supports this inference? Baking soda dissolving; A gas formed, creating bubbles

Which experiment best shows evidence of energy being released in a chemical reaction? Heat and light are given off when paper is burned

Which experiment likely resulted in the formation of a precipitate? Two solutions are mixed together and a yellow solid forms

The BEST evidence for a chemical reaction is the formation of a new substance.

Explanation:

2. When heat and light are being given off, energy is being released. Paper burning is a chemical reaction b/c when paper is burnt, it is a new substance and the act can't be undone.

3. When a yellow solid forms, that solid is the participate.

4. You will for sure have a chemical reaction if a new substance is created.

5. Copper wire changed physically b/c the copper wire can be returned to its original condition in all of these situations and no new substance was formed. Steel Wool changed chemically b/c it can't be returned to its original state under any condition and new substances were formed every time.

6. New substances formed indicate a chemical reaction. A color change also is an indication of a chemical reaction.

7. When a substance can't be turned into its original position or a new substance is produced, a chemical reaction occurred.

Answer:

40.3044 g/mol

Explanation:

hope this helps

Answer:

C. Transition metals

Explanation:

Out of the answers transition metals have the most elements on the periodic table.    

Answer:

the average kinetic energy of its particles increases. When the average kinetic energy of its particles increases, the object's thermal energy increases. Therefore, the thermal energy of an object increases as its temperature increases.

Answer:

Neon is a gas and silicon is a solid i solved this for my chemistry teacher dr Thomas project this week

Explanation:

gasses are naturally less stable then non metalloids

Answer:

390 m

Explanation:

Martha ran 420 m

Cole ran 60 m less than Martha = 420 m - 60 m = 360 m

The distance Kate ran is right in the middle of Martha and Cole's distances

Kate distance = (420 + 360) / 2 = 780 / 2 = 390 m

Answer:

A. mostly ionic

Explanation:

Chemical bonding is the process that links elements together to form compounds