indikator Asam Basa

Telah disebutkan bahwa asam telah mempunyai rasa asam, sedangkan basa telah mempunyai rasa pahit. Namun begitu, tidak dianjurkan untuk dapat mengenali asam dan basa dengan, cara mencicipinya, sebab banyak diantaranya yang dapat merusak kulit (korosif) atau bahkan bersifat racun. Asam dan basa juga dapat dikenali dengan menggunakan zat indikator, yaitu zat yang telah meniberi warna berbeda dahlia) lingkungan asam dan lingkungan basa (zat yang warnanya dapat berubah saat berinteraksi atau bereaksi dengan senyawa asam maupun senyawa basa).

Dalam laboratorium kimia, indikator asam-basa yang biasa di gunakan adalah indikator buatan dan indikator alami, Berikut ini penjelasan tentang indikator asam-basa buatan dan indikator asam-basa alami.
Derajat keasaman (pH)

Indikator Tingkat Keasaman Suatu zat asam yang di masukkan ke dalam air akan dapat mengakibatkan bertambahnya ion hidrogen (H+) dalam air dan berkurangnya ion hidroksida (OH- ). Sedangkan pada basa, akan dapat terjadi sebaliknya. Zat basa yang dimasukkan ke dalam air akan dapat mengakibatkan bertambahnya ion hidroksida (OH- ) dan berkurangnya ion hidrogen (H+).

Jumlah ion H+ dan OH- di dalam air dapat di gunakan untuk dapat menentukan derajat keasaman atau kebasaan suatu zat. Semakin asam suatu zat, semakin banyak ion H+ dan semakin sedikit jumlah ion OH- di dalam air. Sebaliknya semakin basa suatu zat, semakin sedikit jumlah ion H+ dan semakin banyak ion OH- di dalam air.
Proses netralisasi

Apabila suatu larutan asam dengan larutan basa akan dicampurkan dalam suatu bejana, maka ion H+ (dari asam) akan bereaksi dengan ion OH- (dari 311 basa) membentuk air. Reaksi antara ion H+ dengan OH- tersebut juga dapat di tuliskan sebagai berikut. H+ + OH- air

ini karena selain air, basil reaksi antara asam dan basa adalah suatu zat yang bersifat netral, yaitu zat yang tidak bersifat asam maupun basa. Zat netral yang di maksudkan di sini adalah garam. Mengingat reaksi netralisasi juga dapat menghasilkan garam, maka reaksi ini juga di kenal dengan istilah reaksi penggaraman. Secara sederhana, reaksi netralisasi atau reaksi penggaraman juga dapat di tuliskan sebagai berikut.

Contoh sederhana dari reaksi penggaraman adalah reaksi antara asam klorida (HC1) dengan natrium hidroksida (NaOH), yang akan dapat membentuk natrium klorida NaCl (garam dapur) dan air. Pada dasarnya, reaksi penggaraman (netralisasi) juga sangat berguna bagi kehidupan manusia.

Reaksi netralisasi tidak hanya terbatas pada pembentukkan garam dan air. Dalam kehidupan sehari-hari banyak dijumpai prinsip atau reaksi netralisasi, termasuk dalam bidang kesehatan dan pertanian. Perhatikan contoh berikut ini : gas-gas sisa, baik yang berasal dari kendaraan bermotor atau pabrik, mengandung gas belerang dioksida dan nitrogen oksida.

Gas-gas ini akan dilepas ke udara sehingga menimbulkan polusi. Gas-gas tersebut juga akan larut dalam titik-titik air di awan sehingga membentuk larutan asam sulfat dan asam nitrat. Ketika terjadi hujan, larutan-larutan ini akan bercampur dan turun bersama hujan. Inilah yang dinamakan dengan hujan asam.

Hujan asam sangat merugikan manusia dan lingkungan. Berikut adalah dampak yang ditimbulkan oleh hujan asam:

    Hujan asam dapat menyebabkan matinya tumbuhan dan ikan. Asam yang telah terdapat dalam air hujan juga dapat bereaksi dengan mineral dalam tanah. Tumbuhan akan menjadi kekurangan mineral sehingga mati atau tidak tumbuh dengan baik. Hujan asam juga dapat melarutkan aluminium dari mineral dalam tanah dan bebatuan, kemudian menghanyutkannya ke sungai sehingga dapat meracuni ikan dan mahluk air lainnya.
    Hujan asam yang bereaksi dengan logam juga dapat merusak jembatan, mobil, kapal laut, dan rangka bangunan. Hujan asam juga dapat merusak bangunan (gedung/ rumah) yang terbuat dari batu kapur.

Editor : Dian Sukmawati


From sea to shining sea, or at least from one side of the Hudson to the other, politicians you have barely heard of are being accused of wrongdoing. There were so many court proceedings involving public officials on Monday that it was hard to keep up.

In Newark, two underlings of Gov. Chris Christie were arraigned on charges that they were in on the truly deranged plot to block traffic leading onto the George Washington Bridge.

Ten miles away, in Lower Manhattan, Dean G. Skelos, the leader of the New York State Senate, and his son, Adam B. Skelos, were arrested by the Federal Bureau of Investigation on accusations of far more conventional political larceny, involving a job with a sewer company for the son and commissions on title insurance and bond work.

The younger man managed to receive a 150 percent pay increase from the sewer company even though, as he said on tape, he “literally knew nothing about water or, you know, any of that stuff,” according to a criminal complaint the United States attorney’s office filed.

The success of Adam Skelos, 32, was attributed by prosecutors to his father’s influence as the leader of the Senate and as a potentate among state Republicans. The indictment can also be read as one of those unfailingly sad tales of a father who cannot stop indulging a grown son. The senator himself is not alleged to have profited from the schemes, except by being relieved of the burden of underwriting Adam.

The bridge traffic caper is its own species of crazy; what distinguishes the charges against the two Skeloses is the apparent absence of a survival instinct. It is one thing not to know anything about water or that stuff. More remarkable, if true, is the fact that the sewer machinations continued even after the former New York Assembly speaker, Sheldon Silver, was charged in January with taking bribes disguised as fees.

It was by then common gossip in political and news media circles that Senator Skelos, a Republican, the counterpart in the Senate to Mr. Silver, a Democrat, in the Assembly, could be next in line for the criminal dock. “Stay tuned,” the United States attorney, Preet Bharara said, leaving not much to the imagination.

Even though the cat had been unmistakably belled, Skelos father and son continued to talk about how to advance the interests of the sewer company, though the son did begin to use a burner cellphone, the kind people pay for in cash, with no traceable contracts.

That was indeed prudent, as prosecutors had been wiretapping the cellphones of both men. But it would seem that the burner was of limited value, because by then the prosecutors had managed to secure the help of a business executive who agreed to record calls with the Skeloses. It would further seem that the business executive was more attentive to the perils of pending investigations than the politician.

Through the end of the New York State budget negotiations in March, the hopes of the younger Skelos rested on his father’s ability to devise legislation that would benefit the sewer company. That did not pan out. But Senator Skelos did boast that he had haggled with Gov. Andrew M. Cuomo, a Democrat, in a successful effort to raise a $150 million allocation for Long Island to $550 million, for what the budget called “transformative economic development projects.” It included money for the kind of work done by the sewer company.

The lawyer for Adam Skelos said he was not guilty and would win in court. Senator Skelos issued a ringing declaration that he was unequivocally innocent.

THIS was also the approach taken in New Jersey by Bill Baroni, a man of great presence and eloquence who stopped outside the federal courthouse to note that he had taken risks as a Republican by bucking his party to support paid family leave, medical marijuana and marriage equality. “I would never risk my career, my job, my reputation for something like this,” Mr. Baroni said. “I am an innocent man.”

The lawyer for his co-defendant, Bridget Anne Kelly, the former deputy chief of staff to Mr. Christie, a Republican, said that she would strongly rebut the charges.

Perhaps they had nothing to do with the lane closings. But neither Mr. Baroni nor Ms. Kelly addressed the question of why they did not return repeated calls from the mayor of Fort Lee, N.J., begging them to stop the traffic tie-ups, over three days.

That silence was a low moment. But perhaps New York hit bottom faster. Senator Skelos, the prosecutors charged, arranged to meet Long Island politicians at the wake of Wenjian Liu, a New York City police officer shot dead in December, to press for payments to the company employing his son.

Sometimes it seems as though for some people, the only thing to be ashamed of is shame itself.

Finding Scandal in New York and New Jersey, but No Shame

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