Are the “strings” of celery xylem or pholem tissue?

How are exothermic and endothermic reactions linked in the process of refining metal ore?

Alex777 [14]

The intended sense is that of a reaction that depends on absorbing heat if it is to proceed. The opposite of an endothermic process is an exothermic process, one that releases "gives out" energy in the form of heat

6 0

3 years ago

What volume (in milliliters) of oxygen gas is required to react with 4.03 g of Mg at STP?

BigorU [14]

Mg reaction with O₂ gas will produce MgO so the equation will be
2Mg+O₂⇒2MgO. (You have to find the equation in order two figure out the number of moles of O₂ that will react with 1 mole of MgO).

The first step is to find the number of moles of Mg in 4.03g of Mg. You can do this by dividing 4.03g Mg by its molar mass (which is 24.3g/mol) to get 0.1658mol Mg. Then you have to find the number of moles of O₂ that will react with 0.1658mol Mg. To do this you need to use the fact that 1mol O₂ will react with 2mol Mg (this reatio is from the chemical equation) so you have to multiply 0.1658mol Mg by (1mol O₂)/(2mol Mg) to get 0.0829mol O₂. From here you would usually use PV=nRT and solve for V However, the question tells us that we are at STP, that means you can use the fact that 22.4L of gas is 1 mol of gas at STP. Using that information we can find the volume of O₂ gas by mulitlying 0.0829mol O₂ by 22.4L/mol to get 1.857L which equals 1857mL.
therefore, 1857mL of O₂ gas will react with 4.03g of Mg.

I hope this helps. Let me know in the comments if anything is unclear.

6 0

3 years ago

Read 2 more answers

Nault 25000L 250 our = 25000L 15040 8. How many grams of CaCl2 are needed to make 150.0 mL of a 0.500 M CF solution? (Note: CaCl

yuradex [85]

Answer:

You need 8,324 g of CaCl₂ yo make this solution

Explanation:

Molarity is a way to express concentration in a solution, in units of moles of solute per liter of solution.

To know the grams of CaCl₂ it is necessary to know, first, the moles of this substance with the desired volume and concentration , thus:

0,1500 L × $\frac{0,500 mol}{L}$ = 0,075 CaCl₂ moles

Now, with the molar mass of CaCl₂ you will obtain the necessary grams, thus:

0,075 CaCl₂ moles × $\frac{110,98 g}{mol}$ = 8,324 g of CaCl₂

So, you need <em>8,324 g of CaCl₂</em> to make 150,0 mL of a 0,500M solution

I hope it helps!

3 0

3 years ago

A gas exerts a pressure of 4.1 atm at 300K. What is the pressure of the gas at 1010K?

Ainat [17]

Answer: 10

Explanation: 10 + 4.1 = 10

7 0

2 years ago

What would happen to the annual rates of limestone (CaCO3) precipitation in the ocean if the ocean water were to become much war

stiv31 [10]

Answer:

CaCO3 exoskeleton dissolves in acidic water

Explanation:

The increasing CO2 level makes the ocean water acidic and hence reduces the pH. In such acidic environment, marine organism that produce calcium carbonate shells or skeletons are negatively affected. Coral reefs and coralline algae abilities to produce skeleton also reduces.

Calcium carbonate dissolves in acid. Thus, the more acidic the ocean water is the faster and easier it is to dissolve the exoskeleton and shell of marine organisms made up of calcium carbonate

4 0

2 years ago