Answer:
Na sodiops los elementos químicos se representan como el átomo, el núcleo, donde se necuentran los protones y neutrones van dentro, los electrones afuera, girando de forma elíptica alrededor del núcleo. ... por ejemplo el oxígeno numero atómico 8, tiene 8 protones y 8 electrones. el número de neutrones es diferente.
Explanation:
Answer:- 448 mL of hydrogen gas are formed.
Solution:- It asks to calculate the volume of hydrogen gas formed in milliliters at STP when 0.020 moles of magnesium reacts with excess HCl acid. The balanced equation is:

There is 1:1 mol ratio between Mg and hydrogen gas. So, the moles of hydrogen gas is also equals to the moles of Mg reacted.
moles of Hydrogen gas formed = 0.020 mol
At STP, volume of 1 mol of the gas is 22.4 L. We need to calculate the volume of 0.02 moles of hydrogen gas.

= 0.448 L
They want answer in mL. So, let's convert L to mL using the conversion formula, 1L = 1000mL

= 448 mL
So, 0.020 moles of magnesium would produce 448 mL of hydrogen gas at STP on reacting with excess of HCl acid.
Answer:
4 1/2
Explanation:
Use a ratio to find your answer
4 6
----- = -------
3 x
Cross multiply to solve for x.
4x = 18
x = 18/4
x = 4 2/4 which is the same as 4 1/2
Answer:
0.89kg
Explanation:
Q=mL L=specific latent heat
Q=energy required in J
m=mass in Kg
Q=mL
m=Q/L
m=2000000J/2.25 x 10^6 J kg-1
m=0.89kg
Co2 = two covalent bonds
ccl4 = 4 covalent bonds
Lih = covalent bond