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3 years ago

2. Scientist use ________ to measure the distance between stars.

Chemistry

1 answer:

UNO [17]3 years ago

7 0

Scientists use parallax to measure the distance between stars

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Which of the following elements is unreactive argon, germanium, magnesium,sulfur?

MAVERICK [17]

Answer:

Argon

Explanation:

Argon is a noble gas and has a full outer shell of electrons so it doesn't need to form bonds with other atoms as it is stable

7 0

3 years ago

Which body of water will have a greater influence on an area?

Andrei [34K]

Answer:

The correct option is A

Explanation:

Water from a river is used for many activities in a community. These activities could include (but not limited to) tourism, drinking for animals, local transport, irrigation for nearby farming, recreation (as in swimming), habitat for some living organisms among others. Rivers are not limited by what limits the influence of oceans such as taste (it's saltiness, which cannot be used in farming also) and wave current.

5 0

3 years ago

Write the rates for the following reactions in terms of the disappearance of reactants and appearance of products: (a) 302 .....

Oduvanchick [21]

Answer:

Explanation:

$\mathbf{From \ the \ information \ given:} \\ \\ \mathbf{The \ rates \ of \ the \ f ollowing \ reactions \ can \ be \ expressed \ as \ follows:}$

(a)

$\mathbf{3O_2 \to 2O_3} \\ \\ \\ \mathbf{-\dfrac{1}{3}\dfrac{d[O_2]}{dt}=\dfrac{2}{3} \dfrac{d[O_3]}{dt}}$

(b)

$\mathbf{C_2H_6 \to C_2H_4 + H_2} \\ \\ \\ \mathbf{ -\dfrac{d[C_2H_6]}{dt}= \dfrac{d[C_2H_4]}{dt}=\dfrac{d[H_2]}{dt}}$

(c)

$\mathbf{ClO^-+Br^- \to BrO^-+Cl^-} \\ \\ \\ \mathbf{ -\dfrac{d[ClO^-]}{dt}= -\dfrac{d[Br^-]}{dt} = \dfrac{d[BrO^-]}{dt} = \dfrac{d[Cl^-]}{dt} }$

(d)

$\mathbf{(CH_3)_3 CCl+H_2O \to (CH_3)_3COH + H^+ + Cl^-} \\ \\ \\ \mathbf{- \dfrac{d[(CH_3)_3CCl}{dt}= - \dfrac{d[H_2O]}{dt}= \dfrac{d[CH_3)_3COH}{dt}= \dfrac{d[H^+]}{dt}= \dfrac{d[Cl^-]}{dt}}$

(e)

$\mathbf{2AsH_3 \to 2As + 3H_2} \\ \\ \\ \mathbf{-\dfrac{1}{2}\dfrac{d[AsH_3]}{dt}=\dfrac{1}{2}\dfrac{d[As]}{dt}=\dfrac{1}{3}\dfrac{d[H_2]}{dt}}$

5 0

3 years ago

How do double replacement reactions relate to Combustion reactions

andriy [413]

Explanation:

A single-replacement reaction replaces one element for another in a compound.

A double-replacement reaction exchanges the cations (or the anions) of two ionic compounds.

A precipitation reaction is a double-replacement reaction in which one product is a solid precipitate.

Solubility rules are used to predict whether some double-replacement reactions will occur.

3 0

3 years ago

4 Na + O2 → 2 Na2O<br><br> 6.79 moles of O2 will react to form how many moles of Na2O?

Nataly_w [17]

Answer:

13.94moles of Na₂O

Explanation:

The balanced reaction expression is given as:

4Na + O₂ → 2Na₂O

Given parameters:

Number of moles of O₂ = 6.97moles

Unknown:

Number of moles of Na₂O

Solution:

To solve this problem;

1 mole of O₂ will produce 2 moles of Na₂O ;

6.97 moles of O₂ will produce 6.97 x 2 = 13.94moles of Na₂O

6 0

2 years ago