Answer:
Step-by-step explanation:
B) the stone hits the water within the first 2 seconds. Because the stone drops at the speed of 88 feet/second, and 88 x 2 is 176. but the bridge is only 135 feet tall.
so,
88 feet/second
176 feet/2 seconds
135 feet means that it reached the river within 2 seconds. it reached the river in 1.545 seconds
Answer:
36
Step-by-step explanation:
A square has equal sides.
Area= lenth * width
6*6=36
1.326 grams of NH3 are required to produce 4.65 g of HF.
Step-by-step explanation:
Balanced chemical reaction is written first to know the number of moles taking part in original reaction.
NH3 +3 F2 ⇒3 HF + NF3
Given:
mass of HF = 4.65
First the number of moles of HF in 4.65 grams is calculated by using the formula:
number of moles (n) =
atomic mass of HF = 20 grams/mole
putting the values in the above equation number of moles can be found.
n =
= 0.235 moles of HF are given.
From the equation it can be said that:
1 mole of NH3 reacts to form 3 moles of HF
so, x moles of NH3 would react to form 0.235 moles of HF
=
3x = 0.235
x =
x = 0.078 moles of NH3 is required.
The moles are converted to mass by applying the formula:
mass = atomic mass X number of moles (atomic mass of NH3 = 17 grams/mole)
putting the values in the formula
mass = 17 X 0.078
mass = 1.326 grams
To solve for the solution of this system of linear equation, it is best to use substitution. From the first equation, x = 3y
Substituting the expression on the right for the value of x on the second equation,
-2(3y) + 3y = 16
Solving for the value of y gives y = -5 1/3
With this value of y, solving for x gives x = -16
Thus, the solution for this system of linear equation is (-16, -5 1/3)