All categories

2 years ago

I need an answer ASAP

Chemistry

1 answer:

Oduvanchick [21]2 years ago

8 0

Time taken for star to reach Earth = 7.5 years

<h3>Further explanation</h3>

Given

7.5 light years(distance Earth-star)

Required

Time taken

Solution

Speed of light=v = 3 x 10⁸ m/s

1 light years = 9.461 × 10¹⁵ m= distance(d)

So time taken for 1 light years :

time(t) = distance(d) : speed(v)

t = 9.461 × 10¹⁵ m : 3 x 10⁸ m/s

t = 3.154 x 10⁷ s = 1 years

So for 7.5 light years, time taken = 7.5 years

You might be interested in

What refers to the attractive forces that exist between molecules?

CaHeK987 [17]

Intermolecular forces are the forces of attraction or repulsion which act between neighboring particles (atoms, molecules, or ions ). These forces are weak compared to the intramolecular forces, such as the covalent or ionic bonds between atoms in a molecule.

8 0

2 years ago

A sample of CO2 weighing 86.34g contains how many molecules?

irakobra [83]

Answer:

1.181 × 10²⁴ molecules CO₂

General Formulas and Concepts:

Chemistry - Atomic Structure

Reading a Periodic Table
Using Dimensional Analysis
Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Explanation:

Step 1: Define

86.34 g CO₂

Step 2: Identify Conversion

Avogadro's Number

Molar Mass of C - 12.01 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of CO₂ - 12.01 + 2(16.00) = 44.01 g/mol

Step 3: Convert

$86.34 \ g \ CO_2(\frac{1 \ mol \ CO_2}{44.01 \ g \ CO_2} )(\frac{6.022 \cdot 10^{23} \ molecules \ CO_2}{1 \ mol \ CO_2} )$ = 1.18141 × 10²⁴ molecules CO₂

Step 4: Check

We are given 4 sig figs. Follow sig fig rules and round.

1.18141 × 10²⁴ molecules CO₂ ≈ 1.181 × 10²⁴ molecules CO₂

4 0

2 years ago

This was in my chemistry class- What's the color combination code?

Aleksandr-060686 [28]

Blue yellow purple green

3 0

2 years ago

If nitrogen and hydrogen combine in a combustion reaction, what would the product of the reaction be?

kow [346]

Co2

Explanation:

CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (l)

4 0

2 years ago

Read 2 more answers

How many sulfur atoms are there in 3.90 mol of sulfur?

Ilya [14]

In a mole of anything, there are 6.023 x 10^23 units. So, in 3.9 moles of sulfur, there are 3.9 * 6.023 x 10^23 = 23 x 10^23 = 2.3 x 10^24 atoms (keeping only 2 sig figs). Hope I help!!

6 0

2 years ago