KOH + HBr ---> KBr + H2O

0,3 moles of HBr ---in-------1000ml
x moles of HBr-------in------75ml
x = 0,0225 moles of HBr

according to the reaction: 1 mole of KOH = 1 mole of HBr
so
0,0225 moles of HBr = 0,0225 moles of KOH

0,0225 mole of KOH------in-----45ml
x moles of KOH -----------in------1000ml
x = 0,5 moles of KOH

answer: 0,5 mol/dm³ KOH (molarity)

8 0

3 years ago

1) Write the ionic compound formulas for the element sodium and all the elements in group 6A. Example: Sodium + Oxygen=Na2O

PIT_PIT [208]

Answer:

See explanation

Explanation:

1) Group 6A elements include; O, S, Se, Te, Po

Na2O, Na2S, Na2Se, Na2Te, Na2Po

2) Group 7A elements include; F, Cl, Br, I, At

AlF3, AlCl3, AlBr3, AlI3, AlAt3

3) Group 5A elements are;

N, P, As, Sb,Bi

Mg3N2, Mg3P2, Mg3As2, Mg3Sb2, Mg3Bi2

3 0

3 years ago

Neptune is 30 AU (astronomical units) from the sun. How long, in light minutes, would it take for light from the sun to reach Ne

shtirl [24]

Answer:

250 light minutes takes

Explanation:

1 astonomical unit is equal to 1.50x10¹¹m

The light travels at the speed of 3.0x10⁸m/s. That means in 1 second, travels 3.0x10⁸m. To solve this question we must find the distance of neptune to the sun in meters. In this way we can find the seconds (And minutes) that need the light to travel from the sun to neptune:

<em>Distance from Sun to neptune:</em>

30AU * (1.50x10¹¹m / 1AU) = 4.5x10¹²m

<em>Time transcurred:</em>

4.5x10¹²m * (1s / 3.0x10⁸m) = 15000s

15000s * (1min / 60s) =

<h3>250 light minutes takes</h3>

7 0

4 years ago