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3 years ago

Really need help!

2 answers:

7 0

The magnitude of a star as it would appear to a hypothetical observer at a distance of 10 parsecs or 32.6 light-years. This rates how visible celestial bodies are when they are all viewed from the same distance. Luminosity: The brightness of a star in comparison with that of the sun.

vovangra [49]3 years ago

7 0

You might be interested in

Need help with these two pls!!

denis23 [38]

what is a fire piston?

*a tool for starting a fire, likely invented in Ancient Southeast Asia.*

dont know the second one lol.

8 0

3 years ago

How many molecules are in 69 grams of Na?

12345 [234]

Molar mass Na = 23.0 g/mol

1 mol ---- 23.0 g
n mol ---- 69 g

n = 69 / 23.0

n = 3.0 moles

1 mole -------- 6.02x10²³ molecules
3.0 moles ---- ?

3.0 * 6.02x10²³ / 1

= 1.806x10²⁴ molecules

hope this helps!

7 0

3 years ago

Given the balanced equation what is the reaction ?

VMariaS [17]

This is a double replacement reaction; the ions switch twice.

3 0

4 years ago

Explain what air is, where on Earth it occurs, and how it moves to create wind.

pickupchik [31]

Answer:

Wind is caused by differences of pressure in the Earth's atmosphere. Air from a high pressure area will move towards an area of low pressure. High winds are caused when air moves between areas with large differences in air pressure.

Explanation:

4 0

4 years ago

True or False: In every gram of sucrose (table sugar) there is 0.513 g of oxygen

Ber [7]

Answer:

True

Explanation:

Step 1: Find molecular formula of sucrose

C₁₂H₂₂O₁₁

Step 2: Convert moles of oxygen present to grams

1 mol O = 16 g O

11 mol O = 176 g O

Step 3: Find molar mass of sucrose

C - 12.01 g/mol

H - 1.01 g/mol

O - 16.00 g/mol

12.01(12) + 22(1.01) + 11(16.00) = 342.34 g/mol C₁₂H₂₂O₁₁

Step 4: Set up dimensional analysis

$1 gC_{12}H_{22}O_{11}(\frac{176 gO}{342.34gC_{12}H_{22}O_{11}} )$

Step 5: Multiply/Divide and cancel out units

Grams of C₁₂H₂₂O₁₁ and grams of C₁₂H₂₂O₁₁ cancel out.

We are left with grams Oxygen

176/342.34 = 0.514109 grams Oxygen

4 0

3 years ago