1. The force of a surface pushing back on an object is called the ____

sesenic [268]

Answer:

For number 2, your answer is C.

Explanation:

The nucleus is positively charged because the proton is positive and a neutron is neutral. An electron has a negative charge.

6 0

3 years ago

Based on the reactivities of the elements involved, which reaction will form products that are more stable than the reactants?

LUCKY_DIMON [66]

Answer: The correct option is B.

Explanation: All the given reactions are a type of single displacement reactions.

Single displacement reactions are defined as the reactions in which a more reactive metal displaces a less reactive metal in a chemical reaction.

General equation for these reactions is:

$AB+C\rightarrow CB+A$

For the given reactions, we will use the reactivity series. The metal which lies above in the reactivity series will easily displace the metal which lies below in the reactivity series.

Option A: For this reaction, zinc lies below aluminium in the reactivity series. Hence, zinc will not be able to displace aluminium in the chemical reaction.

Option B: For this reaction, Sodium is more reactive than calcium as it lies above in the reactivity series. Hence, sodium will easily displace calcium in the given chemical reaction.

Reaction follows:

$CaBr_2+2Na\rightarrow 2NaBr+Ca$

Option C: For this reaction, hydrogen lies below magnesium in the reactivity series. Hence, hydrogen will not be able to displace magnesium in the chemical reaction.

Option D: For this reaction, Calcium lies below barium in the reactivity series. Hence, calcium will not be able to displace barium in the chemical reaction.

Option E: For this reaction, barium lies below lithium in the reactivity series. Hence, barium will not be able to displace lithium in the chemical reaction.

Reactivity series is attached below.

3 0

4 years ago

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How does water change the shape of Earth's surface?

xz_007 [3.2K]

Answer:

Water moving across the earth in streams and rivers pushes along soil and breaks down pieces of rock in a process called erosion. The moving water carries away rock and soil from some areas and deposits them in other areas, creating new landforms or changing the course of a stream or river.

Explanation:

5 0

3 years ago

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Upon combustion, a compound containing only carbon and hydrogen produces 2.67 g<img src="https://tex.z-dn.net/?f=CO_%7B2%7D" id=

Hoochie [10]

Answer:

$\boxed{\text{CH$_{2}$}}$

Explanation:

1. Calculate the mass of each element

$\text{Mass of C} = \text{2.67 g } \text{CO}_{2}\times \dfrac{\text{12.01 g C}}{\text{44.01 g }\text{CO}_{2}}= \text{0.7286 g C}\\\\\text{Mass of H} = \text{1.10 g }\text{H$_{2}$O}\times \dfrac{\text{2.016 g H}}{\text{18.02 g } \text{{H$_{2}$O}}} = \text{0.1231 g H}$

2. Calculate the moles of each element

$\text{Moles of C = 0.7286 g C}\times\dfrac{\text{1 mol C}}{\text{12.01 g C }} = \text{0.060 67 mol C}\\\\\text{Moles of H = 0.1231 g H} \times \dfrac{\text{1 mol H}}{\text{1.008 g H}} = \text{0.1221 mol H}$