Abeaker contains 0.42 l of water. the beaker’s volume is .

The beaker's volume is 420 milliliters

Explanation:

A beaker contains 0.42 L of water. The beaker’s volume Is ___milliliters.

To solve this,We will simply use proportion;

Let x be the beakers volume in milliliters

1 Liter         =   1000 milliliters

0.42 Liter    =     x

Cross multiply

1×x  =  0.42 ×  1000

x    =   420 milliliters

Therefore the beaker's volume is 420 milliliters

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2

the right answer is c i just did the question.