Answer:
8.1 moles
Step-by-step explanation:
Given parameters: Mass of water to be decomposed = 29.2g Unknown: Number of moles of oxygen. Solution: To solve this problem, we first write the balanced reaction equation : 2H₂O → 2H₂ + O₂ Now convert the given mass of the water to number of moles; Number of moles of water = Molar mass of water = 2(1) + 16 = 18g/mol Number of moles of water = = 16.2moles From the balanced reaction equation: 2 moles of water produced 1 mole of oxygen gas; 16.2 mole of water will produce = 8.1moles of oxygen gas
Hope this helps you :3
Answer:
The numbers 180 and 0 would make the average 90
Step-by-step explanation:
we know that
To find the average of two numbers, add the numbers and then divide by two.
Let
x ----> one number
y ----> the other number
The average is equal to
(x+y)/2
For x=180 and y=0
the average is equal to
(180+0)/2=90
therefore
The numbers 180 and 0 would make the average 90
She can find out answer by dividing 21÷3 and the answer is 7
She can make 7 bird house
Answer:
16) 18.5 hours
Step-by-step explanation:
40gifts = 5hrs
40/5 = 8
8gifts = 1hr
148/8 = 18.5
In 18.5 hours, 148 gifts are wrapped.
hope this helps and is right. p.s. i really need brainliest :)
Answer: -7twice
Step-by-step explanation:
This is a question on root of quadratic equation. The interpretation of the question
x² 14x + 49 is
x² + 14x + 49 = 0.meaning that we are to find two possible values for x that will make the expression equal 0.
We can use any of the methods earlier taught. For the purpose of this class, I am using factorization methods
x² + 14x + 49 = 0
Now, find the product of the first and the last terms, is
x² × 49 = 49ײ
Now find two terms such that their productbis 49x² and their sum equals 14x, the one in the middle.
We have several factors of 49x² but only one will give sum of 14x. Because of the time, I will only go straight to the required factors .
49x² = 7x × 7x and the sum gives 14x the middle terms..
Now we now replace the middle one by the factors and then factorize by grouping.
x² + 14x + 49 = 0
x² + 7x + 7x + 49 = 0
x(x + 7) + 7(x + 7) = 0
(x + 7)(x + 7). = 0
Now to find this value of x,
x + 7 = 0
x. = -7twice.
The root of the equation = -7twice.