40.3 degrees Fahrenheit. Each hour the temperature decreases by 2.09 What is the

In what direction does an applied force move an object?

igor_vitrenko [27]

The answer is B. In the same direction as the force. Hope this helps :)

8 0

3 years ago

Why was the measurement unit for metal content in Experiments 1 and 2 different? In Experiment 1:

olya-2409 [2.1K]

To identify why a metal measurement was different in the experiments look for the variable that was different in the experiment and analyze how this change affected the results.

<h3>What is an experiment?</h3>

An experiment is a procedure that aims at probing or discovering something. For example, you can test if a plant grows faster/slower by using an experiment.

<h3>What causes different results in similar experiments?</h3>

The most common cause for this situation is that one of the factors or variables is slightly different. For example, if I add 50mL of water to a plant rather than 20mL of water every day this might cause different results.

Based on this, if the metal content was different you should analyze if any of the factors changed in this experiment and find out how this change affected the general results.

Note: This question is incomplete because there is limited information about the experiment; due to this, I answered it based on general knowledge.

Learn more about experiments in: brainly.com/question/13270830

8 0

2 years ago

In the laboratory, hydrogen gas is usually made by the following reaction: Zn(s) + 2 HCl(aq) → H2(g) + ZnCl2(aq) How many liters

IrinaK [193]

<u>Answer:</u> The volume of hydrogen gas collected over water is 2.13 L

<u>Explanation:</u>

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of zinc = 5.566 g

Molar mass of zinc = 65.4 g/mol

Putting values in above equation, we get:

$\text{Moles of zinc}=\frac{5.566g}{65.4g/mol}=0.0851mol$

For the given chemical reaction:

$Zn(s)+2HCl(aq.)\rightarrow H_2(g)+ZnCl_2(aq.)$

As, HCl is present in excess. So, it is considered as an excess reagent.

Zinc is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

1 mole of zinc produces 1 mole of hydrogen gas.

So, 0.0851 moles of zinc will produce = $\frac{1}[1}\times 0.0851=0.0851mol$ of hydrogen gas

To calculate the volume of hydrogen gas, we use ideal gas equation, which is:

PV = nRT

where,

P = Pressure of hydrogen gas = Total atmospheric pressure - vapor pressure of water = (752 - 18.65) mmHg = 733.35 mmHg

V = Volume of the hydrogen gas

n = number of moles of gas = 0.0851 moles

R = Gas constant = $62.3637\text{ L.mmHg }mol^{-1}K^{-1}$

T = Temperature of hydrogen gas = $21^oC=[21+273]K=294K$

Putting values in above equation, we get:

$733.35mmHg\times V=0.0851mol\times 62.3637\text{ L.mmHg }mol^{-1}K^{-1}\times 294K\\\\V=\frac{0.0851\times 62.3637\times 294}{733.35}=2.13L$

Hence, the volume of hydrogen gas collected over water is 2.13 L

5 0

3 years ago

How much heat energy must be absorbed to completely melt 35.0 grams of H2O(s) at 0°C?

Cerrena [4.2K]

(35/18.02)(6.02kJ)=11.6926 kiloJoules

5 0

4 years ago

El símbolo del ion que contiene 24 protones, 28 neutrones y 21 electrones es: (Marque con X la respuesta correcta)

mrs_skeptik [129]

Answer:

d) Cr⁺³

Explanation:

Consideremos un ion que contiene 24 protones, 28 neutrones y 21 electrones.

Para encontrar el simbolo del elemento, tenemos que considerar el número atómico (Z) que es igual al número de protones. Con esta información, buscamos en la tabla periódica el elemento con Z=24 es el Cromo.

La carga total está dada por la diferencia entre protones y electrones. Los ´protones tienen carga +1 y los electrones carga -1. Luego, este ion tiene carga:

24 protones + 21 electrones = 24 . (1) + 21 . (-1) = +3

El simbolo del ion es Cr⁺³.

3 0

3 years ago