Answer:
4.05 × 10²² atoms
Explanation:
Step 1: Given data
Mass of nickel: 3.95 g
Step 2: Calculate the moles corresponding to 3.95 g of nickel
The molar mass of nickel is 58.69 g/mol.
3.95 g × (1 mol/58.69 g) = 0.0673 mol
Step 3: Calculate the atoms in 0.0673 moles of nickel
We will use Avogadro's number: there are 6.02 × 10²³ atoms of nickel in 1 mole of atoms of nickel.
0.0673 mol × (6.02 × 10²³ atoms/1 mol) = 4.05 × 10²² atoms
Given:
Concentration of Fluoride ions = 0.100 M
Concentration of Hydrogen Fluoride = 0.126 M
Asked: Concentration of fluoride ions after the addition of 5ml of 0.0100 M HCl to 25 mL of the solution
Assume: 50:50 ratio of fluoride ions and HF
12.5ml*0.1mol/L *1L/1000mL + 12.5*0.126mol/L * 1L/1000mL = 2.825x10^-3 moles F-
5ml * 0.01 mol/L *1L/1000mL = 5x10^-5 moles
Assume: Volume additive
Final concentration = 2.825x10^-3 + 5x10^-5 moles/ 30 ml * 1000ml/L =0.0958 M
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<u>Answer:</u> The correct answer is Option B.
<u>Explanation:</u>
Decomposition is a type of chemical reaction in which larger compound breaks down into two or more smaller compounds.
Double displacement reactions is defined as the chemical reaction in which exchange of ions takes place.
Synthesis reaction is a type of reaction in which two or more smaller compounds combines to form a single large compound.
Single displacement reaction is a type of reaction in which a more reactive metal displaces a less reactive metal from its chemical reaction.
In stomach, an acid is present known as hydrochloric acid and to neutralize its effect, antacid is taken which has 
as a component.
The reaction between HCl and 
is a type of neutralization reaction and it is a type of double displacement reaction.
The equation between the two follows:
Hence, the correct answer is Option B.
Is bubble chamber one of your choices? Bubble chamber sounds like a good fit for the question.
Answer:
D.phototropism
Explanation:
Phototropism is a type of tropism in which a plant or plant part responds to light. According to this question, a student wanted to investigate the effect of light on the growth of cress seedlings. The student used three different pots for the experiment.
Pot 1 was placed with light from above. Pot 2 was placed in a cupboard with no light. Pot 3 was placed in a window with light from one direction only. However, the image attached to this question shows that the plants in the different pots face different directions in response to light, which depicts phototropism
