All categories

3 years ago

If a star is 300 light years away from Earth, how long does it take light from that star to reach Earth?

Chemistry

1 answer:

Salsk061 [2.6K]3 years ago

8 0

Answer: It would take 300 light years to reach Earth.

Explanation:

You might be interested in

4. I'm the "brain" of the cell or so they say. I regulate activities from day to day...

Luba_88 [7]

Answer:

nucleus

Explanation:

it holds information needed to regulate most of the cell functions

6 0

4 years ago

A susbtance has an empirical formula of CrO2 and a molecular weight of 168 g/mol. determine the molecualr formula for this subst

Sunny_sXe [5.5K]

Answer:

$Cr_{2} O_{4}$

Explanation:

$\frac{molecular weight}{molar mass}$ = $\frac{168}{83.99}$ = 2.00

$CrO_{2}$ x 2 = $Cr_{2} O_{4}$

3 0

2 years ago

Using the reaction below: 2 CO2(g) + 2 H2O(l) → C2H4(g) + 3 O2(g) ΔHrxn= +1411.1 kJ What would be the heat of reaction for this

maw [93]

Answer: d) -705.55 kJ

Explanation:

Heat of reaction is the change of enthalpy during a chemical reaction with all substances in their standard states.

$2CO_2(g)+2H_2O(l)\rightarrow C_2H_4(g)+3O_2(g)$ $\Delta H=+1411.1kJ$

Reversing the reaction, changes the sign of $\Delta H$

$C_2H_4(g)+3O_2(g)\rightarrow 2CO_2(g)+2H_2O(l)$

$\Delta H=-1411.1kJ$

On multiplying the reaction by $\frac{1}{2}$ , enthalpy gets half:

$0.5C_2H_4(g)+1.5O_2(g)\rightarrow CO_2(g)+H_2O(l)$ $\Delta H=\frac{1}{2}\times -1411.1kJ=-705.55kJ/mol$

Thus the enthalpy change for the given reaction is -705.55kJ

7 0

3 years ago

In developing his periodic table, Mendeleev listed on cards each element's name, atomic mass, and

forsale [732]

B I think is the answer

4 0

4 years ago

If a gas is kept in a container with a constant volume and the pressure is reduced, how will the temperature of the gas be affec

3241004551 [841]

Answer:

The pressure law states that for a constant volume of gas in a sealed container the temperature of the gas is directly proportional to its pressure. ... This means that they have more collisions with each other and the sides of the container and hence the pressure is increased.

6 0

3 years ago