Can someone please help me i dont understand and im about to get a zero

In which color coded area would you find an element that behaves both like a metal and a non-metal?

Kay [80]

what elements are each color over? can you list one from each color so i can answer it

4 0

3 years ago

A liquid-fueled rocket engine has two liquids, usually called the fuel and the oxidizer. Which two liquids are most commonly use

hammer [34]

Answer:

A liquid-fueled rocket has two liquids (liquids are good because of the density, they need less space than a gas to be stored), such that these liquids are called the fuel and the oxidizer.

These liquids are injected into a system that leads to a combustion chamber, where the liquids are mixed (we need to mix the fuel with the oxidizer to enable the combustion of the fuel) and burned to produce thrust.

Some common examples of oxidizers are liquid oxygen, which may be combined with fuels like liquid hydrogen, liquid methane, kerosene and hydrazine.

Other oxidizers are liquid fluorine (which also can be combined with the fuels liquid hydrogen and hydrazine), nitrogen tetroxide (which can be combined whit kerosene, hydrazine and other fuels) and FLOX-70, which can only be combined with kerosene.

The "most commonly used" may depend on the country and the type of liquid propellant ( petroleum, cryogens, and hypergols)

Such that the most common oxidizer may be liquid oxygen, and the most common fuel the kerosene.

8 0

3 years ago

How are Celsius, Kelvin, and Fahrenheit scales similar? How are they different? Considering their differences, think of one scen

PIT_PIT [208]

Answer:

they are similar becauze they measure temperature

6 0

3 years ago

Consider the following reaction:C2H4(g) + F2(g) -----------> C2H4F2(g) Delta H = -549 kJEstimate the carbon-fluorine bond ene

frutty [35]

Answer:

Bond energy of carbon-fluorine bond is 485 kJ/mol

Explanation:

Enthalpy change for a reaction, is given as:

$\Delta H_{rxn}=\sum [n_{i}\times (E_{bond})_{i}]-\sum [n_{j}\times (E_{bond})_{j}]$

Where $(E_{bond})_{i}$ and $(E_{bond})_{j}$ represents average bond energy in breaking "i" th bond and forming "j" th bond respectively. $n_{i}$ and $n_{j}$ are number of moles of bond break and form respectively.

In this reaction, one mol of C=C, four moles of C-H and one mol of F-F bonds are broken. One mol of C-C bond, four moles of C-H bonds and two moles of C-F bonds are formed

So, $-549kJ=(1mol\times 614kJ/mo)+(4mol\times E_{C-H})+(1mol\times 154kJ/mol)-(1mol\times 347kJ/mol)-(4mol\times E_{C-H})-(2mol\times E_{C-F})$

or, $-549kJ=(1mol\times 614kJ/mo)+(1mol\times 154kJ/mol)-(1mol\times 347kJ/mol)-(2mol\times E_{C-F})$

or, $E_{C-F}=485kJ/mol$

So bond energy of carbon-fluorine bond is 485 kJ/mol

8 0

3 years ago

100 POINTS!!! WILL GIVE BRAINLIEST FOR DETAILED AND CORRECT ANSWER!!!

sveticcg [70]

Answer:

dissolve rocksalt in heated water

Explanation:

If the rock salt is one large chunk, grind it into a powder using a mortar and pestle or a coffee grinder.

Add 30-50 milliliters of water to six heaping spatula scoops of rock salt.

Stir to dissolve the salt.

Place the filter paper in the mouth of the funnel.

Place the evaporating dish under the funnel to collect the liquid.

Slowly pour the rock salt solution into the funnel. Make sure you don't over-fill the funnel. You don't want the liquid to flow around the top of the filter paper because then it isn't getting filtered.

Save the liquid (filtrate) that comes through the filter. Many of the mineral contaminants did not dissolve in the water and were left behind on the filter paper.

Place the evaporating dish containing the filtrate on the tripod.

Position the Bunsen burner under the tripod.

Slowly and carefully heat the evaporating dish. Be careful! If you apply too much heat, you might break the dish.

Gently heat the filtrate until all the water is gone. It's okay if the salt crystals hiss and move a little.

Turn off the burner and collect your salt. Although some impurities will remain in the materials, many of them will have been removed simply by using the difference in solubility in water, mechanical filtration, and by applying heat to drive off volatile compounds.

If you want to further purify the salt, you can dissolve your product in hot water and crystallize the sodium chloride from it.

6 0

3 years ago